So how are we doing on our project to massively increase U.S. wind and solar generation capacity? This chart posted by Stuart Staniford at Early Warning is not reassuring, at least regarding wind.

The American Wind Energy Association’s Q4 2010 market report reveals that new installations collapsed in 2010.

The chart below shows what the U.S. energy mix is today, and what the U.S. Energy Information Agency projects it to be over the next 25 years. The nuclear and coal part of the mix are expected to drop only a bit, coal from 45% to 43% and nuclear from 20% to 17%.

[Note that 43% of 5+ trillion kilowatt hours per year is a lot more than 45% of the 4+ trillion kilowatt hours coal accounts for today - meaning coal consumption in electricity generation is thus expected to increase substantially.  So much for doing anything about global warming.]

The University of California, Berkeley Center for Entrepreneurship and Technology has published a technical brief which considers three scenarios for “maximum penetration” of electric cars into the market, projecting market share of new cars at 2015, 2020, 2025, and 2030 under differing cost assumptions.

The “market” in the above chart is defined as those likely to buy electric vehicles – 20% of the total market is excluded as not likely to buy electric vehicles.

Under the baseline scenario, 81 million electric vehicles would be on the road by 2030; under the operator-subsidized scenario, 151 million.

The U.C. study calculates that by 2030 the fleet of electric cars is estimated to require between 190 and 350 million megawatt hours of electricity per year. Currently, electricity generation in the U.S. totals around 4 billion megawatt hours per year. Powering an electric car fleet would require that the U.S. increase electricity generating capacity by 4.75%-8.75% by 2030. And that’s assuming no growth in electricity usage elsewhere in the economy, despite population and presumably economic growth.

In 2009, U.S. nuclear plants generated 798.7 billion kilowatt hours (or 7,987 million kilowatt hours) from 104 commercial nuclear generating units; “nuclear generating units” in the U.S. thus average 7.68 megawatt hours per year in output. The 602 coal power plants in the U.S. produce on average ~3.88 megawatt hours per year. Powering the projected U.S. electric car fleet would therefore require building 25-46 additional “nuclear generating units” by 2030. Or 50-90 coal-fired power plants.

Renewable sources, including wind and solar, currently account for about 10% of U.S. electricity generation – but two thirds of existing renewable capacity is hydroelectric, which is about tapped out and even under threat of decline. Solar and wind together account for only a little over 2% of renewable electric energy – about 72,000 megawatt hours per year. Powering the projected electric fleet from solar and wind alone would require increasing our solar and wind capacity by a factor of 2,500 – 5,000. Just to power electric cars,  nothing else: no growth, no phasing out of nuclear or decommissioning aging plants, no shutting down of CO2-emitting coal plants.

Phasing out nuclear power while we are still able so to as avoid catastrophic accidents, and phasing out coal to save the planet as we know it, would seem to be of a bit higher priority than powering our go-carts.

Challenging times indeed. Replacing our gasoline-powered cars with electric cars is about the last thing we should be focusing on.

Bill Gross, founder of the Californian company IdeaLab, offers some lessons learned:

• Use software to analyze and optimize performance of plants.
• Don’t build plants – get utilities (customers) to build them.
• Avoid environmental conflicts and transmission line costs by building smaller plants on brownfield sites near cities.
• Leverage energy storage and volume of scale in manufacturing to reduce costs.

Big Gav expands on these points in his post. It’s worth checking out.

On the other hand, John Michael Greer has a post voicing cautionary notes about the prospects for solar:

The first is that familiar nemesis of renewable energy schemes, the problem of net energy. It would take a pretty substantial amount of highly concentrated energy to build that hundred square mile array of mirrors, counting the energy needed to manufacture the mirrors, the tracking assemblies, the pipes, the steam turbines, and all the other hardware, as well as the energy needed to produce the raw materials that go into them – no small amount, that latter. It would take another very substantial amount of concentrated energy, regularly supplied, to keep it in good working order amid the dust, sandstorms, and extreme temperatures of the Nevada desert; and if the amount of energy produced by the scheme comes anywhere close to what’s theoretically possible, that would probably be the only time in history this has ever occurred with a very new, very large, and very experimental technological project. Subtract the energy cost to build and run the plant from the energy you could reasonably (as opposed to theoretically) expect to get out of it, and the results will inevitably be a good deal less impressive than they look on paper.

The second is another equally common nemesis of renewable energy schemes, the economic dimension. . . . If investing billions of dollars (and, more importantly, the equivalent amounts of energy and resources) in mirrors in the Nevada desert doesn’t produce as high an economic return as other uses of the same money, energy, and resources, the mirrors are going to draw the short end of the stick. Political decisions can override that calculus to some extent, but impose an equivalent requirement: if investing that money, energy, and resources in mirrors doesn’t produce as high a political payoff as other uses of the same things, once again, the fact that the mirrors might theoretically allow America’s middle classes to maintain some semblance of their current lifestyle is not going to matter two photons in a Nevada sandstorm.

Stuart Staniford at Early Warning takes issue with Greer, noting that photovoltaic (PV) systems can produce a positive energy return in the range of 4.8–13.9, a range pretty consistent with the findings in this 2009 report that net life-cycle EROEI for PV was in the range of 3.75:1 to 10:1.  Regarding solar thermal, the same report did not give numerical findings, but rather stated:

The energy balance of this technology is highly variable depending on location, thus few studies have been done. In the best locations (areas
with many sunny days per year), EROEI is likely to be relatively high.

Even the most optimistic estimates for thermal energy are a long way from the 100:1 return on energy investment that oil gave in the 1940s – though not quite so far from the 23:1 energy return that oil provided in the 1970s. Oil EROEI has certainly dropped even more today. For example, oil production in deep water currently achieves an EROEI of less than 5. For the production of Canadian syncrude the EROEI is less than one – that is, it takes more energy to produce a barrel of oil than the barrel of oil contains.

If – as Greer suggests – the future is unlikely to fulfill our cornucopian fantasies, the future need not be grim:

When concentrated energy is scarce, local production of relatively diffuse energy for local use is a far more viable approach for a great many uses. This will allow the highly concentrated energies that are left to be directed to those applications that actually need them, while also shielding local communities from the consequences of the failure or complete collapse of centralized systems. The resulting economy may not have much resemblance to today’s fantasies of a high-tech future, but the barbarism Frank Shuman feared is not the only alternative to that future; there’s something to be said for a society, even a relatively impoverished and resource-scarce one, that can still reliably provide its inhabitants with hot baths, warm rooms in winter, and well-done pot roasts – and, of course, good brandy.

The 24 Solar Energy Study Areas, located in Nevada, Arizona, California, Colorado, New Mexico and Utah, encompass about 670,000 acres. Only lands with excellent solar resources, suitable slope, proximity to roads and transmission lines or designated corridors, and containing at least 2,000 acres of BLM-administered public lands were considered for solar energy study areas. Sensitive lands, wilderness and other high-conservation-value lands as well as lands with conflicting uses were excluded. The BLM will temporarily “segregate” the study areas from new mining claims and other actions initiated by third parties under public land laws during the environmental reviews until any final decisions are made.

BLM has provided a map showing solar potential in the four southwestern states:

The plant will use mirrors to focus sunlight on tubes containing liquid, heating the liquid and turning it to steam, which then spins turbines. Molten salt will store heat from the plant so it can keep generating power after sunset.

Joseph Romm at Climate Progress has posted a schematic of the design:

There’s a new article in Environment 360 titled “A Potential Breakthrough In Harnessing the Sun’s Energy” on solar thermal. The article notes solar thermal projects are currently being planned or built in many regions around the globe, including North Africa, Spain, Australia, and the southwestern U.S.

While utility-scale solar thermal projects have provoked opposition due to the large land area occupied by the arrays, it’s hard to see how we’re going to solve our energy and climate change problems without large-scale concentrated solar facilities.

This basic design isn’t nearly as efficient as the Passivhaus – but it’s simple, and can be done cheaply.

This is the concept Irina and I followed when we first renovated our house, which was nothing more than a pole-barn sheepshed converted (badly) into a dwelling, back in 1994.  Fortunately the building was oriented to face the south (which is one of the reasons we purchased the property).  We closed up most of the east- and west-facing windows and enlarged and added windows on the south side, with double-glazed glass. We laid black tile over the concrete slab floor to absorb heat (too bad we couldn’t insulate under concrete, which could easily be done with new construction). Wall insulation was R-19, ceiling R-30. All this was done for a few thousand dollars – cheap (we later replaced the roof with a white steel roof, which added considerably to the cost, and summer performance).

And the house has performed well.  Without any heating or cooling other than a small wood stove, it’s warm and cozy in winter, and cool in summer except for a couple of hours in the late afternoon/early evening on the few very hottest days which a small fan makes tolerable. A couple of cords of wood gets us through the winter.

Starting from scratch would have made it possible to increase performance by better sealing, insulating the floor, and controlling thermal mass more precisely. But then consider all the energy saved by recycling an existing structure. We’re happy with the results.

Solar thermal electric energy generation concentrates the light from the sun to create heat, and that heat is used to run a heat engine, which turns a generator to make electricity. Solar thermal power costs about 18 cents a kilowatt-hour at present,  roughly 40% cheaper than electricity generated by the silicon-based panels. Improved technology and economies of scale are expected to eventually lower the cost of solar thermal to about 5 cents a kilowatt-hour – about the same as carbon-spewing coal, which generates about half the nation’s electricity.

A solar thermal energy industry report says a great advantage of solar thermal over photovoltaic generation – which directly converts the sun’s light into electricity – is that storing heat is far easier  more efficient, and cheaper than storing electricity. Because of the electricity storage problem, photovoltaic solar panels are only effective during daylight hours, whereas heat can be readily stored during the day and then converted into electricity at night.

Florida has broken ground on a solar-natural gas hybrid system that is the first of its kind, utilizing both solar thermal and an existing combined-cycle natural gas plant. When the sun is not shining,  natural gas will power the turbines.

Industrial-scale solar power plants are being built in Nevada . . .

and across the Atlantic on the Iberian penninsula.

The Tennessee Valley Authority wants 2 gigawatts of renewable power – solar, wind, geothermal or tidal – on the ground by June 2011.

Solar electricity still needs to get to people’s homes. On our existing grid, this means power towers and high-voltage lines. But In Europe, the proposed supergrid would employ high-voltage DC (HVDC) technology and underground transmission lines, sidestepping local opposition to conventional overhead AC transmission lines.

Others complain that solar arrays require space – space that gets a consistent amount of direct sunlight.  Solar thermal power plants typically require 1/4 to 1 square mile or more of land – and change the environment on that land.

But are solar arrays better or worse than . . .

oil fields with their related infrastructure?

Appalachian mountaintop removal?

The rape of Alberta?

Hydropower, which we think of as our most environmentally friendly energy source, in the U.S. has displaced species and devastating ecosystems, turned the Columbia from a mighty river into a series of lakes, and drowned Glen Canyon and the Hetch Hetchy Valley.

Solar energy insiders claim that a  patch of desert about 100 miles square could generate enough electricity to meet the entire nation’s demand. Given the alternatives, that sounds pretty benign.

But how credible is this claim? That depends on what is meant by “enough electricity to meet the entire nation’s demand.” Today’s demand? Tomorrow’s demand, assuming energy usage continues to grow at historic rates? What if the transportation sector was to be electrified?

The plausibility of baseload solar power advocates’ claim will be the subject of a future post.

It is highly scalable, eventually able to achieve 50 to 100 gigawatts a year growth or more. And its ultimate trump card is storage. No batteries required, just a heat sink – and the round-trip efficiency is 90%.

Forget the oxymoronic “clean coal.” Concentrated solar thermal will be delivering reliable, low-cost power while “clean coal” will forever remain nothing more than a chimera.

Unlike solar photovoltaic systems that convert sunlight into electricity, this plant will focus sunlight on tubes that contains water. The light heats the water, creating steam, thus turning turbines. Solar thermal plants have an advantage compared to photovoltaic technology because energy can be stored as heat without being converted to another form or relying on batteries.

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Ausra Inc., the developer of utility-scale solar thermal power technology, says the daily and seasonal variation in grid load in the United States matches solar availability and claims solar thermal power could supply over 90% of U.S. grid plus auto fleet.

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 Here’s the auto rickshaw – essentially an enclosed three-wheeled motorcycle. It supposedly gets 82 mpg.

And now it’s going solar.  The solar version can either be pedaled or run on a 36-volt battery. Yahoo! News reports:

“The fully-charged solar battery will power the rickshaw for 50 to 70 kilometres (30 to 42 miles). Used batteries can be deposited at a centralised solar-powered charging station and replaced for a nominal fee.”