New articles and posts

by Richard Perkins

I’ve written a new article on wave power in my renewable energy series over at Associated content. You can also read a copy with figures and pictures on my Professional page or in my Renewable Tech series. Be sure to check it out and let me know if you have any questions.

Renewable Tech – ocean power part 1

by Richard Perkins
This entry is part 5 of 6 in the series Renewable Tech

Waves in Pacifica In this fifth article in my continuing series on renewable energy technology, I’d like to talk about ocean power. The term covers virtually any technology that extracts power from the sea, ranging from fairly well-known wave energy and tidal energy conversion systems to more experimental ideas like ocean thermal energy conversion (OTEC) and salinity gradient devices. In their own way, OTEC and salinity gradient devices are as different from wave or tidal energy converters as PV arrays are from wind turbines. Since the technologies in this group are so different, I’ll cover them in separate articles.

Today’s topic will be wave energy. Countless new technologies have emerged in the wave energy arena since Stephen Salter first threw his hat into the ring over three decades ago with the Salter Duck. They come in a bewildering array of shapes and sizes. How do these wave energy converters work?

Wave energy simplified

Wave energy systems extract useful work from the most visible embodiment of the power in the ocean: waves. Waves are generated by the winds, which induce oscillations at the ocean’s surface. The stronger the wind and the longer it blows along the surface of the water, the bigger the waves. Recall from my first article on hydropower that generators work on the principle of magnetic induction: they generate electricity by spinning a loop of wire in the presence of a magnetic field. Wave energy devices work by transforming the elliptical or circular oscillation of sea water into the rotation of a generator. There’s a staggering variety in the mechanisms used to achieve this transformation. Wave energy systems are usually categorized by three traits: the way they capture wave energy, the way they convert that energy to power, and their location. Individual designs can look radically different from each other, since nearly any combination of the above traits is possible.

Energy capture methods

The options for wave energy capture are so diverse that opinions differ on how to categorize them. Point absorbers are floating devices that move up and down with the waves relative to a mooring or inertial reference. The motion can be used to pump water through a turbine, to spin a generator directly with a mechanical linkage, or to drive a linear electric generator. Point absorbers have been used successfully for years in unmanned navigation buoys. Companies like Ocean Power TechnologiesFinavera Renewables and CETO Technology are developing products for utility scale power generation using arrays of point absorbers.
Attenuators, or surface following devices, are long devices with multiple segments, like floating train cars facing into the oncoming waves. As the segments bend relative to each other from variation in wave height along the length of the train, this motion can be used to turn a generator, through a mechanical linkage or by pumping a fluid through turbine. Pelamis is developing one of the best known examples of an attenuator device, and installed just over 2 MW of capacity in the Agucadoura wave farm in 2008.

Terminators are wave energy devices that extend across the wave front, perpendicular to the direction of wave travel (like the direction a surfer travels in a pipeline). Some terminators, like OceanLinx device, funnel the incoming wave energy into an oscillating water column which pushes air through a special turbine that spins in the same direction regardless of the direction of air flow. Other terminator devices use a different strategy call overtopping, where the waves slosh water up ramps into a reservoir. The sea water drains out of the reservoir through a turbine which drives a generator. Wavedragon deployed a prototype of such an overtopping device in 2003 off the coast of Denmark and is currently preparing to deploy a full scale prototype with a 7 MW capacity.

There are other types of wave energy converters a well, unique designs that don’t fit in any of the above categories. Like oscillating wave surge convertors, devices with paddle-like arms that wave back and forth around a pivoting joint as the waves pass over them. Aquamarine Power’s Oyster and BioPower Systems’ BioWave are examples of this energy capture method, though they differ in their approach to power take-off.

Power take-off methods

As if there weren’t enough variety in energy capture method, there are also several aproaches used to convert the captured wave energy into useful power. Some systems use hydraulic conversion methods, pumping sea water through a turbine using hydraulic rams or hose pumps. Hydraulic rams feature a piston in a cylinder with an inlet valve and an outlet valve. As the piston withdraws from the cylinder the inlet valve opens and low pressure sea water is drawn into the device. As the piston reverses direction and compresses, the inlet valve closes and the pressure in the cylinder increases. When the pressure exceeds a threshold the outlet valve is forced open and high pressure sea water is pumped out of the cylinder to a water turbine. Hose pumps deliver high pressure water by mimicking the human digestive tract. Rollers propagate a constriction along the length of a flexible hose, which create high pressure ahead of the pinch point and low pressure behind it. In both cases the high pressure sea water is pumped through a turbine to drive a generator.

If the turbine is located with the device, then electric power is transmitted to shore through sub-sea electric cables. Alternatively, the wave energy device can pump high pressure sea water to the shore instead, where it will drive an on-shore turbine and generator.

Some systems use air turbines to drive a generator instead of water turbines. Oscillating water column devices fall into this category.

Other systems rely on a direct mechanical coupling to a spin a generator or to drive a linear electric generator. These devices usually house the generator at sea with the wave energy device and transmit electric power to the shore via sub-sea electric cables.

Location

To add to the spectrum of technical development in the wave energy conversion space, devices can be located in different zones as well. Shoreline systems are located at the beach. Some terminator type devices require solid mooring and are often located on the shoreline. There are near-shore devices, which are optimized for operation in shallow water. And some devices are classified as off-shore, designed for operation in deeper waters farther out to sea.The boundaries between near-shore and off-shore are a little hazy, but systems designed to work in 10-20 meters of water will not operate well in 50-70 meters of water, and vice versa.

State of the art

Wave energy technology, though over thirty years old, is still not as mature as wind energy or solar PV. The biggest symptom of this is the diversity of technologies still under development. The industry hasn’t converged toward an optimal design solution or even on a handful of optimal design solutions. The main challenges that face the wave energy industry are survivability, efficiency of energy capture, and regulatory hurdles, both environmental and recreational. All of these challenges drive up the cost of deploying wave energy projects, and have (so far) prevented the field from approaching competitive footing in any but the most expensive niches in the electric utility market.

The big elephant in the room though, is survivability. The marine environment is a harsh one, and not just because of salt-water’s corrosive properties. The areas with some of the best wave resources also suffer from hurricanes and typhoons. Designing to withstand such severe storms leads to large and expensive structures like off-shore oil drilling platforms, but oil has a much higher energy density than ocean waves, and the economics just don’t support wave energy devices that expensive.

Some companies, like Sydney’s BioPower Systems, are trying to get clever about this problem with innovative design approaches. In BioPower’s case they are developing biomimetic designs which borrow from nature to improve survivability. But it’s still early days for all of the companies in this space.

Who will find the right combination of innovation and engineering to bring wave energy into the mainstream? Only time will tell. My next article will cover tidal and ocean current energy systems.

The text of this article was previously published on Associated Content.

The first greens of summer

by Richard Perkins

garden1 Ahh, the first greens from our garden! We went away for the weekend to dance at Camp Jitterbug. I was worried that the garden would wilt away in our absence without anyone to water it. Evidently though, the plants are well enough established now that they can go several days without watering.

In fact, the cilantro (the tallest shoot on the left) is climbing like Jack’s beanstalk! The arugula (or rocket, as our Aussie friends say) is also growing well. It’s even starting to flower (until I clipped off the heads to keep the edible leaves growing).

garlic-harvestOur little vegetable plot is only 40″ x 80″. You can see most of it in the picture above. We live in a rented townhouse, so we don’t have room to plant much more. I try to get the most I can out of the space we have. Last month I harvested the garlic we grew over the winter. It’s the first time I’ve grown garlic. The planting, growing and harvesting was easy. However, my attempts to weave attractive garlic ropes were not nearly as successful… ;-)

The summer crop is a bit more diverse. The first row on the left has two bell pepper plants in the back, hidden behind the tall cilantro plant, with two little jalapeno pepper plants in the front. The second row is a line of six green bean bushes. The third row has an eggplant vine hiding in the back, with a tall clump of arugula in the middle, and three little snap pea plants in the front. You can just see part of the fourth row in the picture, which has alternating red and silver swiss chard (silver beat if you’re from down under). You can see a wire trellis off to the right for one of the tomato plants. There’s a second tomato trellis, a zuccini trellis, some more snap peas, and a sweet basil plant that aren’t in the photo.

In the last few days we’ve had chard and rocket leaves on sandwiches and burgers. Beauty mate! Produce doesn’t come much more fresh and local than your own back yard. I do love summer. Can’t wait for the tomatoes to come in. Hopefully with the fence up this year, Bella won’t eat them all before we can pick them. :-)

A copy for myself

by Richard Perkins

Open BookThe submission package for The Renegade’s Door has been in Tor’s in-box for 39 days, according to my delivery confirmation. I don’t expect to hear back from the acquisition editors for some time yet. According to their online guidelines, my submission would only be 20-30% of the way through the slush pile cue by now.

Why then am I writing about Renegade again today? I have another deadline looming. By participating and successfully completing NaNoWriMo last year, I won a certificate for a free proof copy of the book from Print-On-Demand publisher CreateSpace. The catch is that I have to redeem the certificate by June 1st. So I’ve been working on refining the manuscript with input from a college friend who works as a copy editor. I’ve also dragged my sister, an artist turned school teacher, out of painting retirement to create some cover art insired by one of the critical scenes in the novel.

The project is coming together very well. CreateSpace’s guides for self publishing and content creation are very user friendly. In addition, the tools available to the average user today for destop publishing can create some truly professional looking results.

I wrote Renegade using PageFour. This affordable software package is streamlined and optimized for the creative writing process. I’m a big fan, and plan to use it for my next novel as well. One its main advantages as a creative writing tool (it’s lack of distracting features and bug prone tools) is also a drawback for graphic design, layout and publishing efforts.

Fortunately, PageFour RTF files are fairly universally compatible with all major word processors. I simply exported my manuscript from PageFour and formatted fonts, paragraph styles, chapter headings, and other layout options in Word. I could have achieved the same results using OpenOffice freeware, but I already have Word installed on my machine.

CreateSpace accepts only PDF file formats. Newer versions of microsoft Word can generate PDF files, but my Office 2003 installation is a bit too dusty for that feature. Adobe’s Acrobat is the industry standard of PDF generators, but at $300, it was well outside my target price range. I read favorable reviews of PrimoPDF, a freeware PDF generator. Unfortunately, when used in conjunction with Word 2003, the resulting PDF page size was always letter size regardless of the page size set in Word. I didn’t plan to print an 8.5 x 11 paperbook, so PrimoPDF wasn’t an option. I found the solution in PDF Converter, a free online PDF generator that will convert between PDF and a variety of standard Office file formats. Unlike Primo, Pdf Converter maintained all of my custom page size, font and style formatting.

The final step to complete is the cover. CreateSpace offers a couple of options. You can create your own cover art from scratch using a downloaded template file and a graphic editor like Adope Photoshop. Again, if the Photoshop approach is outside of your price range, there are freeware options available for editing and generating a PDF cover art file. One of the simplest is CreateSpace’s very own Cover Creator, an online tool which has a large selection of layouts with customizable fonts, pictures, colors, and syles.  My wife alread owns Photoshop, so I’ll be using a hybrid approach, formatting my sister’s painting into a PDF with good resolution and slotting it into a Cover Creator template online for some of the text and titles.

The process has been enlightening, giving me a better appreciation for the work that a publisher has to do to get a novel into shape for distribution. Hopefully the finished product will look like a real novel when I’m done. Even if I never find a traditional publisher who wants to pick up Renegade, I’ll have a copy or two to put on my shelf and give to the handful of friends who helped me get this far. In addition, I could always sell the title myself through CreateSpace’s E-Store and Amazon.com if I can’t find another market for the work.

Though if I can’t find a traditional publisher who will accept Renegade, there’s probably a reason. In that case, selling a bad book myself won’t help me build a reputation as an author… ;-)

Henry Coe State Park – Backpacking into the Orestimba Wilderness

by Richard Perkins
This entry is part 4 of 6 in the series Trail Guides

The NarrowsSpring is definitely in the air here in northern California. And this time of year I always start to feel an old, familiar itch: the desire to get seriously lost in the woods, right and proper. During a recent conversation about my plans for a trek into the Orestimba Wilderness, a friend raised one eyebrow knowingly and said, “Oh… you’re one of those crazy marathon hikers, aren’t you?”

I shook my head automatically as I started to reply, but my wife nodded before I could deny it. Everyone chuckled. That conversation still makes me think. I don’t consider the kind of trekking I do marathon hiking, per se. Though my longer excursions may be upwards of 30-50 miles, I rarely hike more than 10-12 miles in a single day. On the other hand, the through hikers that plow through the Appalachian Trail, or the Continental Divide Trail, or the Pacific Crest Trail in a single season routinely hike more than 20 miles per day. And they maintain that pace for months on end. That’s marathon hiking to me, and that’s just plain crazy. But I guess that only proves that crazy is relative.

My latest bout with insanity was a 42 mile, solo backpack trip at the end of April. I was returning to enjoy some of Henry Coe State Park’s 87,000 acres of terrain and 400 miles of trails. My first visit was far too short to see everything, so this trek would take me to some of the park’s less accessible sights.

Hello TomDay 1 of my 5 day, 4 night adventure took me through the Western Zone and into the Blue Ridge Zone. As I did on my last hike in Henry Coe, I followed the single track Corral Trail to its junction with Springs Trail 0.6 miles south east of the park headquarters. Then I continued along the pleasantly graded Springs Trail to its junction with Manzanita Point Road at 1.8 miles. Broad and sunny Manzanita Point Road carried me past the Manzanita Point Group Camps and Bass Pond (and a very handsome wild turkey who posed for a photo) before I turned northeast onto China Hole Trail at 2.7 miles. I met one other backpacker on her way out of the park as I descended through 1000 feet of elevation along the chaparral perfumed switchbacks of China Hole Trail. While I sat on the shore of picturesque China Hole for lunch at 5.2 miles, two other backpackers passed through on their way to Los Cruceros camp.

This is one of the best parts about Henry Coe. After these three friendly greetings, I didn’t see another human for four days. I literally felt like I had the entire park to myself, and it was glorious. After lunch, I turned my back on China Hole’s inviting swimming holes, and headed into the Narrows, a one mile long meander along the east fork of Coyote Creek. The Narrows doesn’t have a maintained trail, but following the creek’s path through the stone walled valley isn’t challenging, as long as you’re up for a little rock hopping along the way.

Bear Mountain RoadI turned my feet northward along Coyote Creek after leaving the Narrows, waving to the two backpackers who were setting up their camp for the night at Los Cruceros. I crossed over into the Blue Ridge Zone at 6.5 miles as I passed the intersection of Narrows and Shafer Corral trails. The rest of my hike for the day was a leisurely stroll along the grassy banks of Coyote Creek. At 8.6 miles I passed the turn-off for Blue Ridge Road and Rock House Canyon Road to the west as I continued northward along Bear Mountain Road. This trail is an old jeep road, which crosses and recrosses Coyote Creek as it wends its way northwest toward Bear Mountain. I continued steadily along the dusty gravel path, enjoying the spring wildflower blooms that carpeted the valley floor as I passed turn-offs for Little Long Canyon Road and a couple of private property holdings. At 10 miles, Bear Mountain Road leaves Coyote Creek and the level valley floor behind as it begins a steep ascent into the park’s Interior Zone. I found a nice level spot near the babbling creek at the foot of the first climb and set up camp for the night. I spent the rest of the evening making notes in my journal and enjoying a tasty dinner. That was Day 1 of my Orestimba Adventure: 10 miles, 1700 feet of elevation loss, 3 hikers, and one tom turkey.

day-1-map

Brrr!I awoke on Day 2 to find a thick layer of silvery frost on my bivy, and a shelf of ice in my water bottles. The temperature had dipped below freezing for much of the night, and I hadn’t even noticed. After a quick breakfast, I packed up and hit the trail. Unlike the single track trails throughout the park, Bear Mountain Road was graded more for vehicles than for mere mortals. The first ascent of the morning was a grueling 1000 feet in less than a mile. After crossing over into the Interior Zone and attaining the ridge at 1.2 miles (11.2 trip miles), Bear Mountain Road continues northwest toward the 2604 foot summit of its namesake. This entire area is still recovering from the Lick Fire that burned over 47,000 acres in 2007. New tufts of green are sprouting around the charred black branches of chaparral and color is marching  its way across the dry hills. There is no shade to be had on this leg of the hike, but the views are unobstructed for miles. So bring your sunglasses, a hat, sunscreen, water, and take plenty of breaks if you decide to make the trip.

Blooming thistleI reached the summit of Bear Mountain at 2.8 miles (12.8 trip miles), passing Bear Mountain Peak Trail and two branches of Bear Spring Trail that wound south through the Interior Zone toward Mississippi Lake. After the strenuous climb up to the ridge, the summit itself was a bit anticlimactic. But it did mean that I had completed most of my climbing for the day. Just beyond the summit I reached County Line Road, an wide jeep trail that marks the border between Stanislaus and Santa Clara counties, and also the divide between the Pacheco Creek and Coyote Creek watersheds.

Here I turned north, which took me through a gated fence at 3 miles (13 trip miles) onto one of the private property carve-outs in the park. If you travel this high ridge, be sure to respect the land owner by sticking to the road and not lingering. Not that I had much choice but to stay on the road. This northern part of the Interior Zone if sliced up by steep sided ridges. County Line Road teeters along a knife-edge, the only viable route for miles around. Again the views are magnificent, but you wouldn’t want to be there too long under a relentless late summer sun, so plan accordingly.

Old Hayseed RoadAt 4.1 miles (14.1 trip miles), just after crossing out of the private property, I turned east at an overturned trail marker, and officially entered the Orestimba Wilderness Zone. The Chaparral Trail, or Old Hayseed Road as I came to think of it, is another unmaintained jeep road, steep and rugged. The chaparral hasn’t grown back after the fires yet, and the trail is filling in with tall, dry grasses. These wild grasses are laden with seedpods eagerly awaiting any opportunity to burrow their pointy way through socks and the linings of hiking boots. The 1.8 mile long trail descends through 1000 feet into the broad valley of Red Creek. The last half mile features a daunting 20% grade, so tighten up your laces before the final descent.

Red Creek RoadAt 6 miles (16 trip miles) I crossed over the dry stream bed of Red Creek onto Red Creek Road. I sat on the creekbank to rest and remove the hayseeds from my socks and shoes. 45 minutes later I finally gave up the effort and turned southeast along Red Creek Road. Like my walk through the Blue Ridge Zone on Day 1, this was a pleasantly level stroll along the floor of a wide river valley carpeted in wild grasses and the occasional burst of wildflower color. But unlike Coyote Creek, Red Creek was mostly dry along this 4 mile stretch. There were still standing pools water to be found stranded near the undercut boulders along the stream bank or sheltering in the partial shade of rocky cliff faces. But running water was scarce. If you’re headed this way, pack accordingly.

SunbathingAt 7.8 miles I passed the unmarked Grass Trail to the north. I continued southwest, following Red Creak Road as it veered northeast away from Red Creek and into the low hills at the western end of Paradise Flat. A little lizard was there to greet me, basking in the afternoon sun. This mile long valley is bordered to the north and south by creek beds and was once the site of a airstrip. (I wasn’t able to find any remaining sign of it though.) The valley is a broad sea of rippling golden grains that sway in the breeze like waves, complete with green islands of venerable, wizened oak. Red Creek Road hugs the northern edge of this idyllic savanna.

Paradise Lake TotemAt 9.5 miles (19.5 trip miles) I reached the turn-off for Paradise Lake, a man-made water feature penned into a narrow valley at the southern foot of Robinson Mountain. The lake is tucked into the surrounding mountains such that you can’t see it from anywhere in Paradise Flat. You just turn off Red Creek Road on a dusty trail that winds north into the hills, and scramble down a short but steep descent to find yourself on this gorgeous little piece of… well… of paradise. This was my camp for the night, so I had reached the end of Day 2: 10.2 miles (20.2 trip miles), 1700 feet of elevation gain, 1800 feet of elevation lost, miles of views, and one lizard.

day-2-map

Day 3 was a rest day for me. I slept in, swam in the lake, stayed for lunch, and spent several hours working on plot lines and character descriptions for my next writing project. It was a relaxing day, spent in the company of the lake’s resident population of american coots and red-winged blackbirds. But in the interest of making my return trip a little easier, I packed up my camp in the early afternoon and left Paradise Lake behind me.

dscn0126I returned to Red Creek Road and continued east. I reached Orestimba Creek Road at 1.2 miles (21.4 trip miles), where I turned south. Much like Red Creek, Orestimba Creek was mostly dry, with occasional standing pools of stranded water on the sunny valley floor. At 1.5 miles (21.7 trip miles) I passed a signed turn-off for the Long Ridge Road, which leads east to Jackrabbit Lake. My destination was further south.

Unfortunately, the Mustang Pond Trail was not signed or marked in any way. But I did find it, a narrow side canyon with a trickling rivulet of water at 2.2 miles (22.4 trip miles). This route wasn’t so much a trail as it was a wild game path, leading to the dam of Mustang Pond at 2.7 miles (22.9 trip miles).

Mustang PondLike Paradise Lake, Mustang Pond is a man made reservoir, with its own captive population of large mouth bass. But where Paradise Lake is surrounded by the steep walled ridges of Mount Robinson, Mustang Pond is cupped in gently rolling hills in the northern part of the Mustang Peak Zone. The banks of the pond are much more accessible, with foot paths all the way around its shoreline. The bass were bigger and much more active while I was camping here than at Paradise Lake, striking the surface regularly to dine on the evening’s bugs. Of the two sites, Mustang Pond is probably the better destination for fishermen. (Too bad I didn’t bring my pole.) But it wasn’t quite as scenic as Paradise.

At 2.7 miles (22.9 trip miles), 200 feet of elevation gain and 300 feet of elevation lost, Day 3 wasn’t much of a hike for me. But it put me in a good position for the return trip I had planned.

day-3-map

I was up early on Day 4, and had eaten, cleaned up, and broken camp by 7:30. The southern branch of the Mustang Pond Trail was much more open and easy to follow than the northern route. There had clearly been horses through the area recently and someone had left helpful tape flags on tree limbs along the trail to mark the way. At 0.4 miles (23.3 trip miles) I rejoined the Orestimba Creek Road and continued southwest. The road returned to the banks of Orestimba Creek at 1 mile (23.9 trip miles) and followed the dry gravel of the stream bed to the junction with Hartman Trail at 1.9 miles (24.8 trip miles), where I crossed back into the Orestimba Wilderness Zone. Hartman Trail is not maintained, but wasn’t difficult to follow as it climbed west through the valley of a small tributary of Orestimba Creek.

View from Hartman TrailAt 2.4 miles (25.3 trip miles) the Hartman Trail leaves the wooded stream bed behind and begins a steep, mile-long ascent through mixed chaparral and chamise. I stopped after climbing through 1000 feet of elevation to reach a small promontory at 2210 feet with excellent views of the Orestimba and Robinson Mountains. Then I pressed on, dropping through a saddle before climbing back up to County Line Road at 4 miles (26.9 trip miles).

I followed County Line Road north for 0.1 miles before turning west again into the Mississippi Zone at the road that crosses Mississippi Lake’s dam. The hills surrounding this large man-made lake are lush and green, but water access is limited. I climbed down to the water’s edge near the western end of the dam, where I stopped for a short rest at 4.4 miles (27.3 trip miles). Rather than continue west when I reached the junction with Willow Ridge Road 0.2 miles later, I followed the jeep road that contours along the lake’s western shore. This well traveled, fully wooded road wends northward within constant sight of the lake’s blue waters, but never actually gets down to the shoreline until it reaches a picnic area on the northern cove at 5.7 miles (28.6 trip miles).

Mississippi Lake

I stopped at the picnic area to eat lunch, wait out a brief but cooling rain shower, and to refill my water bottles. Then I continued north until I reached an unmarked branch of Bear Mountain Peak Trail, which I ascended to a scenic ridgeline overlooking the entire lake. The rain showers returned during this leg of the trip, but it was a light mist that cooled the air and brought out the fresh smells of chaparral and chamise, so I didn’t mind. I put a raincover on my pack and continued south on the Peak Trail to it’s junction with Willow Ridge Road at 7 miles (29.9 trip miles), where I turned southwest once again.

The rain continued throughout the rest of Day 4, which was very agreeable during the hike. Willow Ridge Road and the single track Willow Ridge Trail are sometimes called the roller coaster, and with good reason. The southern section of the Interior Zone is banded with steep ridges, much like the northern section. This jeep road climbs up and down as it traverses a narrow, often knife-edged ridge, with views that stretch forever. Most of the walk is shadeless, and would have been hot and sweaty on a sunny day. Lost wrecking ballBut the light rain and the high clouds made for cool, pleasant hiking and views that stretched for miles. I startled a black-tailed deer and shared the road with an inquisitive jack rabbit, passing Caviata Spring Trail, Pacheco Ridge Road, and Pacheco Creek Trail along the way. Near the turn-off for Rat Spring Trail at 10.2 miles (33.1 trip miles) I found a curious landmark, a large, worn wrecking ball lying forgotten in a field of wildflowers.

At 11 miles (33.9 trip miles) I reached the signed intersection with single track Willow Ridge Trail. Here I turned northwest to descend through heavy oak trees whose wet leaves dripped quietly in the spring rain and whispered serenely in the mountain breeze. Half a mile into the Western Zone, after slogging through rain soaked grasses and passing by a decidedly green Willow Ridge Spring, I arrived at my camp site for the night. The light rain, which had been such a boon during the hike, intensified as the evening wore on, falling in sheets that I watched marching across the ridges to the west. The rain didn’t let up until after midnight, bringing my Day 4 to a rather waterlogged end with 11.6 miles (34.5 trip miles), 3000 feet of elevation gained, 1900 feet of elevation lost, one black-tailed deer and one jackrabbit. (I warned you that Willow Ridge Road was a roller coaster, didn’t I?)

day-4-map

Day 5 dawned cool and partly cloudy, but free of rain. I changed back into my wet gear to preserve some dry clothes for the drive home, and broke camp after breakfast. I returned to the Willow Ridge Trail and turned east, descending through alternating black oak and chaparral. The single track trail descends through switchbacks across former ranch lands, losing 1000 feet of elevation in a little over a mile on its way to Los Cruceros at 1.7 miles (36.2 trip miles).

Soda SpringsBack on familiar ground again, I crossed through the Narrows to China Hole. But instead of returning up China Hole Trail, I turned southwest down Coyote Creek on the Mile Trail. This densely forested single track trail follows the Soda Springs tributary of Coyote Creek west  from China Hole. I crossed and recrossed the merrily flowing stream several times along the Mile Trail, passing a thick stone walled root cellar set into the hillside on the northern edge of the stream and a collapsed hunting lodge straddling the stream just before reaching the Madrone Soda Springs trail camp at 4 miles (38.5 trip miles). Here I turned north onto the Madrone Soda Springs Trail, which ascends 800 feet up a steep ridge through switchbacks.

I stopped for lunch at the Manzanita Point Group Camps at 5 miles (39.5 trip miles) where I ran into the first campers I had seen in four days. I lost count of the day hikers and wild flower viewers I ran into on this final leg of the trip. After lunch I continued northwest along Manzanita Point Road to its intersection with the shaded Forest Trail at 5.7 miles (40.2 trip miles). This contour hugging single track trail is a pleasant alternative to the sunny Manzanita Point Road and took me back to the Corral Trail at 6.9 miles (41.4 trip miles). I ended Day 5 back at park headquarters: 7.5 miles (42 trip miles), 1900 feet of elevation gain, 1400 feet of elevation lost, and a return to civilization.

day-5-map

This trek was a wonderful escape for me, and a great return to nature for a few days. But it was definitely strenuous, and not for the faint of heart or the out of shape. There are many ways to enjoy Henry Coe State Park. If you live in the Bay area, I invite you to plan a trip as soon as you can get away. Go ahead, find your own wild side.

The text of this article was previously published on Associated Content.

Third strike – still out

by Richard Perkins

It’s official. I have once again snatched defeat from the jaws of victory. It’s been just over a week since my second round interview with a local geothermal technology company. Today I contacted the recruiter for an update, only to find that the company has decided to go with another candidate.

What was the deciding factor this time? Availability. I have no one to blame but myself really. I have some short trips planned in May and June, and a family visit scheduled for July. Before I started interviewing for this position, I had also made a commitment (to myself) to write another novel in July.

I’ve probably said it before: I am not a fast writer. When I’m working, I target 1500-2000 words per day, which takes me about 3-4 hours of uninterrupted writing time. It’s difficult to maintain a pace like that while working a full time job. It would have been easiest for me to start the new engineering position in August, but I did offer to start immediately as long as I could cut back on office hours in July. After reviewing their proposed project schedule and near term milestones, I knew that I could achieve all of their objectives working half days in July and full time there-after. I felt confident about that then and I still do now.

Sadly, they didn’t bite. The recruiter asked on two separate occasions whether my previous commitments were avoidable. But if they were avoidable they wouldn’t be commitments, now would they? And would you really want a program manager who reneged on previous commitments for the sake of expediency?

I think that a commitment you make to yourself is every bit as important as one you make to someone else. I’ve spent the last three years forcing myself to learn that delicate balancing act. It was one of the many reasons I left the semi-conductor industry in the first place. I was in very real danger of losing myself completely in the job. I needed to get out before I burned out.

Well… I’m still out. And this is the third renewable energy job that I have gotten close enough to taste, only to have the oasis turn into a mirage before my first sip. Sometimes you can’t win for losing… :-(

Preparing for a novel marathon

by Richard Perkins

Feather QuillIf you’re one of my regular visitors, you know that I completed my first National Novel Writing Month last November, and submitted The Renegade’s Door to my first potential publisher in April after four months of revision.

If you’re just tuning in for the first time… welcome to the insanity ;-) . Renegade is out in search of its own success or failure, and for the time being, its destiny is out of my hands. So it’s time to turn my attention to the next book. As author Holly Lisle often says, if you want to be an author, “your career lies in writing a book, and writing another book, and writing a book after that.”

So. Onward. But how exactly does one prepare to write a book? I’m no expert, and from what I have read everyone has their own methods when it comes to writing fiction. I’ll tell you how I’m approaching my next novel, and  how I got ready for the last one. It may not work for every aspiring author, but it might work for you. If not… try something else :-) .

For my next novel I’ll be staying in the same world I developed for Renegade, Doormakers’ Fall, and Voices of the Deep. This is an arbitrary choice on my part, but I have my reasons. The world already exists, complete with maps, rules of nature, and a timeline of significant historical events and characters. But perhaps most importantly, one of the characters introduced in my last novel has a story to tell.

In fact ever since Renegade ended, Eliza has been prodding at my subconscious mind in cryptic conversations like this one.

“Hey… yeah you!”

“What… who are… wait a minute. I know you. What are you doing in my office?”

“More importantly what are you doing in your office? Or should I say what aren’t you doing…”

“This is insane… I’m going insane… ”

“Get over it. You do know that you’re not done… right?”

“Not done? What are you talking about? I just sent out the manuscript!”

“I know that! Why do you think I let you slide this long?”

“Slide? Slide! Oh wow… am I really having an argument with a fictional character?”

“Very funny. Yes slide, as in take a break. Well your ember kissing break’s over pal!”

“You might want to be bit nicer to me. You do remember what happened to my last protagonist don’t you?”

“Did you… how… do you think I could forget?”

“I… I’m sorry Eliza. If there was any other way to end it…”

“Yeah. I know. But it’s not over. Did you think you could just leave me in the desert!”

“Leave you? I didn’t leave… you’re with Kenbo and Kenji!”

“Oh great. Thanks so much for that!”

“What’s that supposed to mean?”

“Get back to work and I’ll tell you. You know where to find me.”

“Wait! Where did she…”

There have been lots of little quips like that over the past few months. Even if I did want to write a different story, I’m not sure Eliza would let me. Sometimes it’s nice to have opinionated characters. So I’m gearing up for another dive into the Doormakers’ world, this time with Eliza as my guide.

NaNo was an excellent motivator for me to get through the first draft of Renegade, so I’m going to try to duplicate my success by participating in JulNoWriMo. Between now and July 1, I’ll be laying the groundwork for Eliza’s story. This involves a lot of navel gazing, and endless conversations with Eliza. The first step is to discover the overall story arc.

This is tricky. Eliza knows some of it, but can’t (or won’t) tell me everything. So I try to tease out the direction of the plot by asking what she wants to achieve, starting with the last place I left her at the end of the previous book. Some of her goals are pretty obvious, but there are complications or obstacles that come up. Her efforts to overcome those challenges leads to new goals, new issues, and new character interactions. Some of her goals are long term. Some of them conflict directly with the historical timeline of the world. I have to tread lightly around issues like that, and let Eliza make her opinions known but respect the requirements of the world in which she lives.

This process is iterative. It can take days or weeks. I recently took my journal with me on a long backpacking trip and spent several isolated days penning potential story arcs. What I’ve got so far is coming together, but there are still pieces where I’m not happy with the causality or the flow just doesn’t feel right yet. When I hit a wall like that I describe the pertinent section of plot to friends whose opinion I trust. I listen to their impressions. And then I tinker. And tinker some more. For me this is the most creative part of the novel writing process. It forms the foundation of my outline (and yes, I do write from outlines).  Getting this part right is essential.

After I have the story arc sketched out, my next step is to write character and setting descriptions. The story arc tells me which characters and locations are needed to move the story to its conclusion. For me these descriptions usually start with pictures. Sometimes I use pictures of friends and family. Other times I look for inspiration from photos on the web: faces, clothing, buildings, landscapes, animals both familiar and exotic.

The third step for me is developing scenes and prioritizing them. The story arc is usually developed chronologically: an obstacle is overcome in order to attain a goal, which leads to the next obstacle and the next goal, etc. But the first scene chronologically may not be the most important scene, and it might not be the first scene in the book. Some scenes are historical background, important for character development and context but not critical for moving the action forward. These scenes can be referred to in dialog or possibly used as flashbacks to balance the pace of more intense parts of the narrative. Some scenes (especially in epic multi-character works) happen simultaneously in different geographical locations, and you have to make choices about how much of each scene to reveal to your readers and when to reveal it. It can get complicated. Personally, I put my scenes on 3×5 cards, each with a one sentence description and a scene title (possibly color coded if I’m feeling abitious). Then I move the cards around on a white board until I have a skeleton story outline that I’m happy with.

Once my scene board is up, I start outlining, adding details to the one sentence blurbs in the skeleton until I have encapsulated the setting, the characters involved, how they are going to interact, the focus or intent, and the key change that signals the end of one scene and the beginning of the next. Some authors don’t like using outlines because it feels too confining, or limits their creativity. If they can write novel length fiction extemporaneously like that, more power to ‘em. Personally, I need a road map. I choose to look at story arc building and outlining as my best opportunity to embed creativity in the story.

This becomes really critical when you are participating in a novel marathon like NaNo or JulNo. Generating 1500-2000 words per day every day and getting to the end of your story in just 30 days is difficult enough without writing blind. Which begs the following question: why do it? That’s easy. Before NaNo I spent over a year writing a story without mapping, planning, and outlining it first. I was constantly writing myself into dead ends. And I also kept falling into the trap of rewriting previous scenes before writing new ones. After more than a year I had about 90,000 words and only half of a novel. It wasn’t a total loss: now I think of that period as a giant world building exercise that helped me grow the Doormakers’ world.

By contrast, after NaNo I had a 54,000 word first draft, a complete novel from start to finish. I’ll never write blind again. And the structure of a deadline helps too. What’s my next deadline? June 30th: outline, scene board, character and setting descriptions for Eliza’s story, the sequel to The Renegade’s Door. Maybe then Eliza will let me get some sleep. :P

Henry Coe State Park – Hiking the Blue Ridge Zone

by Richard Perkins
This entry is part 3 of 6 in the series Trail Guides

SkyroadsI finished my first foray into Henry Coe State Park in mid April. It was a short trip into the Blue Ridge Zone, hence the name of the article. I used this trip as prep work for the longer trek I planned for late April (more on that trip in a subsequent post). After taking the winter off, it felt great to hit the trail again.

Let me preface this article by saying that Henry Coe State Park is immense. With 87,000 acres of terrain and over 400 miles of trails, it is the largest State Park in northern California. With fewer than 100,000 visitors annually, it’s a great place to get into the back-country and enjoy some real isolation. It’s convenient and accessible to Bay area outdoor enthusiasts, and less than an hour away from the hustle of South Bay.

I arrived at the park headquarters entrance around 11 AM on a Friday before a weekend that promised unseasonably sweltering weather. The park is divided into 12 back-country zones, each with its own unique topography. With some helpful advice from the friendly volunteer rangers, I decided to hike straight through the Western Zone on my way to the slightly less traveled Blue Ridge Zone. Unlike the easily accessible and correspondingly popular Western Zone, where camping is restricted to designated sites, trekkers can camp wherever they want in Blue Ridge. That’s the kind of camping for me.

Rest your feet a spellMy 17 mile round trip started at the park headquarters, a retrofitted ranch house perched on a ridge with sweeping views deep into the heart of the park. I hiked along the pleasantly shaded Corral Trail to its intersection with the slightly more exposed Springs Trail. Springs Trail followed a gently descending contour that afforded glimpses down into Soda Springs water shed to the south before returning to Manzanita Point Road. I then followed Manzanita Point Road through the horse and group camps, stopping to eat lunch at a shaded park bench near the picturesque Bass Pond about 2.5 miles from HQ.

Shortly beyond Manzanita Point, the descent began in earnest. The single track China Hole Trail runs down the ridge through switchbacks cut into shadeless chaparral. China HoleI lost 1000 feet of elevation in two miles on my way to the scenic stone swimming hollows of China Hole. I was 5 miles into the trip at this point, and still in the Western Zone, but it was time to leave the trails behind for a spell.

The Narrows, a rocky 1 mile canyon carved by the east fork of Coyote Creek, has no maintained trail. But it’s still the main thoroughfare between the designated campsites at China Hole and Los Cruceros. It’s also a very agreeable spot of rock hopping, for the kid in all of us. After leaving Los Cruceros, I turned north along the Narrows Trail, finally crossing over into the Blue Ridge Zone 6.5 miles into the trip.

The Narrows Trail meanders along a wide and pleasant valley, crossing and recrossing the east fork of Coyote Creek. It’s an idyllic stretch of trail, and features potential camp sites too numerous to count. Since I hadn’t traveled far enough to settle down yet, I continued north. I found two deep and inviting swimming holes: one north of Arnold Horse Camp and one near the intersection of Little Long Canyon Road, and Bear Mountain Road. Unfortunately for me, I wasn’t the first camper to think so. Each swimming hole had a solitary tent pitched nearby. I decided not to spoil their view by setting up mine when the rest of the evening and the whole of the Blue Ridge Zone was open to me.

Wildflowers in Little Long CanyonAfter traveling a mile up both Bear Mountain and Little Long Canyon Roads to take in the scenery and some wildflowers, I had traveled about 9 miles for the day. I returned back down to the intersection of Blue Ridge Road, Rock House Ridge Trail, and the Narrows Trail. I turned my feet westward and began my climb Blue Ridge Road. 10 miles from where I started, I bushwhacked down into the aptly named Rock House Canyon and found a delightful campsite for the night, complete with my very own private swimming hole.

After dinner, I settled in for the night, content to let the chirp of the frogs and gurgle of the stream lull me to sleep. But before the stars came out I had a visitor. A black tale deer wandered down the creek, grazing his way to within 30 or 40 yards of where I lay awake in the grass, quietly watching. I didn’t have my camera handy, so no photos for me unfortunately. I could see the young buck’s antlers starting to grow in for the summer, still covered in velvet. After he trotted off into the meadow on the far side of the creek, I watched the stars come out overhead until sleep dragged my heavy eyelids closed.

You might think one close encounter would be enough for a short trip, but I woke the next morning to find a second deer cautiously exploring near my camp. This one was a doe, and like the buck from the previous night, she grazed along the edge of the stream to within 30 or 40 yards of me. She eventually trotted up into the meadow on her own and I got up to make breakfast. I headed up into the meadow between Rock House Ridge Trail and the stream myself to see what all the fuss was about. The scene was gorgeous, waves of golden grasses undulating in the morning breeze, dotted with stands of oak , and 360 degree views of the mountains all around. Not a bad way to start the day, no?

Blue Ridge RoadOn my way back to the camp site I saw a flash of tan in the calf high grasses ahead. A hunting coyote dashed across the hillside below me and disappeared. Again, I was caught without my camera. I broke camp quickly and continued my climb back up toward the park headquarters. For the return trip, I followed Blue Ridge Road to Poverty Flat Road. Unlike the single track hiking trails I had taken on the way in, these routes are wider jeep roads, and aren’t as well graded for foot traffic as they could be. There weren’t as many switchbacks on the steep climbs, which resulted in shorter mileage. The jeep roads also were more exposed, and Saturday was definitely the hotter of the two days on this trip.

Pools at Poverty FlatI climbed back up along Blue Ridge Road to the intersection with Poverty Flat Road  at 11 miles. That was a climb from 1300 feet to 1800 feet in less than a mile. Unfortunately I lost all that by mile 13 in the rapid descent to the middle fork of Coyote Creek at the Poverty Flat Camp. The camp had 10-15 tents set up, from a single youth group judging by the looks of mutinous dissent I saw on the group of boys toiling their way up to Poverty Flat in front of a few tired looking pack parents. Poverty Flat Camp is located beside another great water feature in Coyote Creek, a deep pool of crystal clear water surrounded by craggy and charismatic boulders. I just hope the kids are able appreciate their good fortune after they return from their trip.

After leaving the camp, I continued along Poverty Flat road, climbing relentlessly from 1200 feet to 2200 feet at the intersection with the Forest Trail at mile 15. It was a sweat inducing, calf stretching, and mostly shadeless climb. If the climb didn’t take your breath away, the scenery would. But it’s not a trip for the faint of heart (or the out of shape).

California PoppyThe last leg along the Forest Trail was a shady and pleasant stroll by comparison. This close to the headquarters, I was starting to run into day hikers again. One couple warned me that they had seen a big rattle snake lying in the trail ahead, and they had almost stepped on it. I spent the next half mile scanning the ground alertly and listening for the tell-tale buzz in the grass. But all I saw was a little fella sunning himself in the sand as the Forest Trail rejoined Manzanita Point Road just after mile 16. He didn’t do anything more sinister than dart his tongue at me a few times. I continued along the wide, sunny jeep road for the last mile to return to the headquarters, stopping along the way to get some pictures of the Dove Lupine and California Poppy blooms dotting the hillside.

It was a great, if short trip. For hiker’s who really want to get away from it all without going far from the Bay, I can’t recommend the jewel of a state park highly enough. You can see the topographical map of the entire hike, including the elevation profile below (click for a larger, more legible image).

Blue Ridge Zone Topo Map

A text only version of this article was previously published on Associated Content.

New articles and news

by Richard Perkins

I recently started writing for Associated Content. You can find the articles I’ve written here. Please click on over to support my writing habit. I’ve republished all of my Renewable Tech series articles there, although without the embedded images and figures I’ve used on my own web site. I’ve published a fourth article now on geothermal power, so be sure to check it out, either at AC or on my Professional page.

On the novel submission front, Tor has received my manuscript, according to the delivery confirmation system at the US Postal Service. That means I should have news back from them by mid October. (Potentially a rejection letter just in time for NaNoWriMo… hmm… could be a motivation drain for next NaNo…)

On the work front I had a fairly promising interview with a local geothermal technology company this week. It’s too soon to say whether it will go anywhere or not, but I’m cautiously optimistic. More news on that later!

Renewable Tech – geothermal power

by Richard Perkins
This entry is part 4 of 6 in the series Renewable Tech

dry_steam_geysersThis is the fourth article in my continuing series on renewable energy technology, which I published previously here on Associated Content. Today I’ll be talking about geothermal energy. Like wind and hydropower, most geothermal systems are electromechanical in nature: they generate electricity by spinning loops of conductive wire in the presence of a strong magnetic field. Unlike wind and hydro however, geothermal systems are also thermodynamic in nature: they rely on the coupling between temperature, pressure, and volume in a working fluid exposed to an external heat source. They’re actually much more similar to coal, nuclear, and natural gas burning power plants than other renewable technologies.

Have I lost half of you yet? If you’ve read my previous articles in this series, you probably stayed with me through the electromechanical and spinning loops buzzwords. But a thermo-what? A what-dynamic? A what-what? Let me take a step back. Just how do geothermal power systems work?

Geothermal power simplified

In order to understand geothermal power stations, you have to know a little bit about thermodynamics. I’ll keep it as brief and painless possible, I promise. Let’s start with a substance we all know and love: water. Water is liquid at room temperature and atmospheric pressure. So it doesn’t have a fixed shape, but does have a pretty fixed volume. To prove this to yourself, fill a balloon with water, squeeze out all the air, and squish one side of it between your fingers. It bulges out on the other side right? If you squeeze too hard, the balloon breaks: fixed volume, variable shape.

Steam, water’s gaseous phase, doesn’t have a fixed shape or a fixed volume. You can expand it into a large volume or compress it into a smaller one by playing with the pressure, or by heating or cooling the steam. These parameters are thermodynamically coupled. Heat the steam up while maintaining constant pressure and it expands. Conversely, if you cool the steam down at constant pressure it contracts.

What happens if you heat water to well past its boiling point but don’t allow it to expand? By sealing it inside a cylinder for example? You get extremely high pressure water that will turn into a jet of steam at the first opportunity. Now imagine that one wall of this cylinder is actually a piston. Can you see where this is going? If you increase the pressure inside the cylinder enough (by adding enough heat) the water will vaporize, expand into steam, and move the piston. If the piston is attached to a crank which produces useful work by turning a shaft, you’ve built yourself the first half of a simple heat engine.

Of course now your piston is full of steam at fairly high temperature but low pressure, which isn’t particularly useful. In the second half of the cycle the steam will be ejected from the cylinder and allowed to cool and contract to its original state so you can repeat the process all over again.

Traditional power stations, like coal, natural gas, and nuclear plants use this process to transform heat energy into mechanical energy. They then use electromagnetic induction (a loop of conductive wire spinning in a magnetic field) to transform that rotating mechanical energy into electricity to power our utility grid. Sometimes they use fancier stuff than water as a working fluid. And sometimes they use turbines instead of reciprocating pistons, but the underlying concept is the same.

1) Heat a fluid until it changes phase into a gaseous state.

2) Allow the fluid to expand through a controlled mechanism which will extract mechanical power.

3) Let the fluid cool and contract back to its original state (by exhausting heat somewhere convenient) and repeat.

4) Use the mechanical power to drive a magnetic induction generator.

In traditional power plants, the heat come from burning a fuel like coal or natural gas, or from a controlled nuclear fission reaction. Waste heat (an inescapable byproduct of any thermodynamic engine) is dumped into the air or into a large body of water near the plant. In geothermal systems, the heat comes from the earth. But even though geothermal power technology is very similar to the workhorse power stations modern utilities rely upon (coal, gas, nuclear) less than 0.5% of the world’s electricity supply comes from geothermal sources.

That’s largely because getting access to the heat in the earth’s crust is challenging. Traditional geothermal plants must be built near a hydrothermal resource: a geological formation where heat from the earth’s core rises close enough to the surface to heat a reservoir of trapped water. Formations like this tend to occur near the  edges of tectonic plates, regions where volcanoes, earthquakes and hot springs are commonly found. Power plants built on hydrothermal resources fall into three basic categories.

Dry steam geothermal plants

drysteamDry steam plants are built where underground hydrothermal reservoirs are filled with steam rather than liquid water. These plants are called “dry” because the working fluid never changes phase. The steam remains in its gaseous state throughout the thermal cycle. High pressure steam is brought to the surface through a production well in order to drive a turbine directly. Once the steam has expanded through the turbine, it can be pumped back down into the reservoir through an injection well. This is the oldest type of hydrothermal plants, first used in Italy in 1904, and still used in The Geysers complex of power stations in northern California.

Flash steam geothermal plants

flashplantIn flash steam systems, the water in the reservoir is heated beyond its boiling point but under such high pressure that it remains in its liquid state. This hot, high pressure liquid is brought to the surface through a production well and injected into an intermediate pressure tank. Some of the water vaporizes, and the resulting steam drives a turbine, which drives the generator. Sometimes the flashing is done in multiple stages to extract as much energy as possible from the thermofluid. As with the dry steam plant, after passing through the turbine, the low pressure steam can be pumped back down into the reservoir through an injection well. This is the most common type of hydrothermal plant in operation today.

Binary cycle geothermal plants

binaryplantIn a binary cycle plant, the hot water from the reservoir is brought to the surface through a production well and pumped back down into the injection well. But the geothermal fluid never passes through a turbine. Instead, it passes through a heat exchanger along with a secondary fluid that boils at a much lower temperature. The heat from the geothermal fluid flashes the working fluid into vapor which drives the turbine. This approach offers some advantages: the geothermal fluid, with its corrosive minerals deposits and pollutants, never comes into contact with the turbines or generators, and binary systems can be built on resources with lower reservoir temperatures than dry steam or flash systems. For these reasons, most new geothermal plants built on hydrothermal reservoirs will probably be binary cycle plants.

Enhanced geothermal systems

The hydrothermal systems described above all require existing underground reservoirs of hot water or hot steam. There aren’t that many places in the world where all the geological factors required to form such reservoirs come together. But there is abundant heat just a few kilometers below the surface all over the world. We just have to get to it. This is the aim of Enhanced Geothermal Systems, or EGS. Sometimes called Hot Dry Rock or Hot Fractured Rock geothermal, EGS projects drill injection bore holes into deep hot rock using techniques first developed for natural gas and oil field exploration. If the hot dry rocks aren’t porous enough, hydraulic stimulation techniques (also initially developed for gas and oil field exploration) can be used to fracture the rock. The result is a porous bed of hot rock which can be flooded with water through the injection wells, effectively creating an engineered hydrothermal system. Once the new reservoir is filled, a production well is drilled and a power station constructed at the surface. Depending on well pressure and temperature, the EGS plant may be a flash steam system, or a binary cycle system.

EGS may just be the future of the geothermal power industry. I’d be happy to see it knock coal out of the number one spot in the world’s energy portfolio, but that dream is probably still a decade or two away. There are technology hurdles to overcome, like affordable hard rock drilling techniques, and cost effective resource exploration, just to name a few. But EGS offers us possibilities no other renewable energy technology can: greenhouse gas free power that can be built anywhere, that can run 24/7, and that has the same production capacity as similarly sized coal, natural gas, or nuclear plants. Hey, what’s not to love?

This article was previously published without images and figures on Associated Content here.