R-Squared Energy Blog

Pure Energy

Electrifying the USPS

I usually scan the energy headlines each morning, but had somehow missed the stories on the recently introduced bills to electrify the U.S. Postal Service fleet:

U.S. Postal Service to test a repurposed electric vehicle fleet

Rep. Gerald E. Connolly (D-Va.) introduced a bill Friday that would pay for 109,500 electric vehicles, though the cost of that program isn’t known yet. “This, to me, would be a very productive thing and . . . likely to produce jobs and revitalize an industry,” Connolly said.

In December, Rep. José E. Serrano (D-N.Y.) announced an “e-Drive” bill that would give $2 billion to the Energy Department and Postal Service to convert 20,000 mail trucks into electric vehicles.

I have always liked the idea of electric cars. I have written a number of essays around that theme, primarily because electric vehicles could in theory be adequate replacements for internal combustion engines as supplies of fossil fuels deplete. Imagine that our electric grid eventually moves more toward renewable energy, and electric vehicles could be a much greener solution than the majority of the vehicles we have on the road today.

But note that I use words like “theory” and “imagine” to describe this idealistic future. I firmly believe that we need to have a look at the data from time to time to make sure that our idealism isn’t in direct contrast to reality. Unfortunately, in this case it might be.

Study: Electric cars not as green as you think

The environmental benefits of electric cars are being questioned in Germany by a surprising actor: the green movement. But those risks don’t apply in the U.S., the American electric-car lobby asserts.

Today, the German plants that deliver marginal electricity are fueled by coal. That is the main problem, according to the study. The research adds that to produce the same amount of energy, coal emits more carbon dioxide than even gasoline.

“The irony is that you don’t need a lot more electricity for electric cars,” Raddatz, said. “But the problem is that if they cause these peaks, we would have to have power plants that would be ready to start (as) the massive charging starts.”

An electric car with a lithium ion battery powered by electricity from an old coal power plant could emit more than 200g of carbon dioxide per km, compared with current average gasoline car of 160g of carbon dioxide per km in Europe, according to the study. The European Union goal for 2020 is 95g of carbon dioxide per km.

I have been thinking about this a lot, as I have recently seen some electric car/combustion engine comparisons in a report that is about to come out. I won’t divulge much about the report, but when it comes out I will link to it. But I will provide a quote from the soon-to-be-released report:

New Zealand energy consultant Steve Goldthorpe estimates that if the entire New Zealand vehicle fleet were replaced with electric cars, the amount of electricity New Zealand needed to generate to power this fleet would be increased by about 60%. Only a small percentage of this electricity could be produced sustainably; the balance would probably have to be generated by burning coal.

I think this is where idealism clashes with reality. As I pointed out in The Nuclear Comeback, over the previous 10 years electricity demand increased by an average of 66 million megawatt hours per year. That is without adding electric cars to the mix. The growth rate for renewable energy over the past 5 years or so has only been about 10 million megawatt hours (although last year saw an impressive 20 million). Still, this is a far cry from just keeping up with normal demand growth.

So the idealistic side of me sees renewable electricity continuing to grow, and powering a fleet of green electric cars. The side of me that looks at the data says that in reality, a rapid ramp-up of electric cars will have to be driven by non-renewables because renewable energy growth won’t be able to keep up. I wouldn’t personally have a problem with a nuclear-driven electric fleet, but I don’t think that’s the vision many have for future electric vehicles.

I am not factoring in the possibility that conservation of electricity can help close that gap. On that I remain hopeful, but our history is one of ever increasing consumption.

March 5, 2010 Posted by | electric cars, electricity, electricity usage, nuclear energy, renewable energy | 1 Comment

Prices of Various Energy Sources

As we continue to develop biomass as a renewable source of energy, it is important to keep the cost of energy in mind, because this has a very strong influence on the choices governments and individuals will make. I sometimes hear people ask “Why are we still using dirty coal?” You will see why in this post.

Last year I saw a presentation that projected very strong growth in wood pellet shipments from Canada and the U.S. into Europe. My first thought was “That doesn’t sound very efficient. Why don’t we just use those here in North America?”

It didn’t take very long for me to find out the answer to that. It is because wood pellets are much more expensive than natural gas in North America. On top of that it takes more effort to use wood for energy than it does natural gas. That combination means that wood has a tough time competing with natural gas in North America.

When I was looking into that issue, I compiled a list of the price for various energy types on an energy equivalent basis. The price is as current as possible unless noted. I have converted everything into $/million BTU (MMBTU), and the sources are listed below.

My preference is to use EIA data over NYMEX data because the former is an archived, fixed number. I have included energy for heating and for various transportation options. For comparison I also included the cost of electricity and the cost of the ethanol subsidy/MMBTU of ethanol produced.

Current Energy Prices per Million BTU

Powder River Basin Coal – $0.56
Northern Appalachia Coal – $2.08
Natural gas – $5.67
Ethanol subsidy – $5.92
Petroleum – $13.56
Propane – $13.92
#2 Heating Oil – $15.33
Jet fuel – $16.01
Diesel – $16.21
Gasoline – $18.16
Wood pellets – $18.57
Ethanol – $24.74
Electricity – $34.03

Observations

It isn’t difficult then to see why wood pellets have a difficult market in the U.S. For people with access to natural gas, they are going to prefer the lower price and convenience of natural gas over wood. For Europe, their natural gas supplies aren’t nearly as secure, so they have more incentive to favor wood as an option.

The cost of the ethanol subsidy is interesting. We pay more for the ethanol subsidy than natural gas costs. However, if you consider that we are paying a subsidy on a per gallon basis – and a large fraction of that gallon of ethanol is fossil fuel-derived, the subsidy for the renewable component is really high.

For instance, if we consider a generous energy return on ethanol of 1.5 BTUs out per BTU in, that means the renewable component per gallon is only 1/3rd of a gallon. (An energy return of 1.5 indicates that it took 1 BTU of fossil fuel to produce 1.5 BTU of ethanol; hence the renewable component in that case is 1/3rd). That means that the subsidy on simply the renewable component is actually three times as high – $17.76/MMBTU. Bear in mind that this is only the subsidy; the consumer then has to pay $24.74/MMBTU for the ethanol itself.

Sources for Data

Petroleum – $13.56 (EIA World Average Price for 1/08/2010)
Northern Appalachia Coal – $2.08 (EIA Average Weekly Spot for 1/08/10)
Powder River Basin Coal – $0.56 (EIA Average Weekly Spot for 1/08/10)
Propane – $13.92 (EIA Mont Belvieu, TX Spot Price for 1/12/2010)
Natural gas – $5.67 (NYMEX contract for February 2010)
#2 Heating Oil – $15.33 (EIA New York Harbor Price for 1/12/2010)
Gasoline – $18.16 (EIA New York Harbor Price for 1/12/2010)
Diesel – $16.21 (EIA #2 Low Sulfur New York Harbor for 1/08/2010)
Jet fuel – (EIA New York Harbor for 1/12/2010)
Ethanol – $24.74 (NYMEX Spot for February 2010)
Wood pellets – $18.57 (Typical Wood Pellet Price for 1/12/2010)
Electricity – $34.03 (EIA Average Retail Price to Consumers for 2009)

Conversion factors

Petroleum – 138,000 BTU/gal
Gasoline – 115,000 BTU/gal
Diesel – 131,000 BTU/gal
Ethanol – 76,000 BTU/gal
Heating oil 138,000 BTU/gal
Jet fuel – 135,000 BTU/gal
Propane – 91,500 BTU/gal
Northern Appalachia Coal – 13,000 BTU/lb
Powder River Basin Coal – 8,800 BTU/lb
Wood pellets – 7,000 BTU/lb
Electricity – 3,412 BTU/kWh

January 19, 2010 Posted by | coal, EIA, electricity, Energy Information Administration, ethanol prices, ethanol subsidies, gas prices, oil prices | 1 Comment

Book Review – Power of the People

I will finish up my long-promised concluding post in the recent series on ethanol and oil imports. I have been traveling for ten days, and inadvertently left all of my graphics for that post on another computer. I am back home now, and will try to tidy it up and post it in the next few days.

On the long plane ride back to Hawaii, I read Power of the People: America’s New Electricity Choices. I picked this book up at the 2009 Solar Tour – Pikes Peak Region, which I visited on my trip to Colorado. My new job has me getting more involved in the electricity sector, and I thought this would be a book that would help push me up the learning curve. A short description of the book:

America is as addicted to electricity as it is to oil. Our electricity usage increases every year, yet we still use the same transmission grid that was constructed in the middle of the last century. The grid is stretched to the limit, creating the potential of future black-outs like the one that brought the Northeast to its knees in 2003. Meanwhile, some of our most abundant and affordable generating fuels have become major culprits in global warming.

Power of the People explores in a nontechnical, conversational way some of the clean, green, 21st-century technologies that are available and how and why we should plug them into our national grid. This important essay explores our failure as a country to adopt these “no regrets” technologies and policies as swiftly as the rest of the world, and why it matters for the future of every American.

The author, Carol Sue Tombari, works for the National Renewable Energy Lab (NREL). Despite trying, I can’t find out what her exact position or qualifications are. Here biography says:

Carol Sue Tombari has specialized in energy and environmental policy and programs for more than 25 years. She directed the State of Texas’s energy efficiency and renewable energy programs, served as natural resources advisor to the lieutenant governor, and helped found the National Association of State Energy Officials.

In addition, she was appointed to federal advisory posts by two Federal Secretaries of Energy, chairing a Congressional advisory committee on the subject of renewable energy joint ventures and serving on the U.S. Department of Energy’s (USDOE) State Energy Advisory Board. Tombari is employed at the USDOE’s National Renewable Energy Laboratory, where she works on local and rural economic development. Ultimately, it is her love for the next generation that continues to drive her work to protect the future of our planet and the lives of those yet to come.

While I found myself learning more about the sector, many things she said left me puzzled. For instance, she claimed that the U.S. uses more energy per GDP than anyone else in the world. This is exactly the opposite of Jeff Rubin’s claim in Why Your World Is About to Get a Whole Lot Smaller. Rubin claimed that countries like China use a lot more energy per GDP, which was the basis of his argument that carbon tariffs could work in favor of countries like the U.S., who are more energy efficient at producing GDP. In fact, if you look at the EIA data on energy usage per dollar of GDP, you can see that the U.S. is on the low end of the scale. According to the EIA data, China, compared to the U.S., uses about four times the amount of energy per dollar of GDP. (Thanks to reader Clee for that reference).

The book is pretty anti-nuclear, and makes the claim that renewables are “considerably more affordable” than nuclear power. She seems to rely on Amory Lovins and Tom Friedman for these sorts of claims. The book is pretty realistic about coal, however, concluding that we will be relying on coal for a good many years. She did claim, though, that there have been no major technological innovations in coal-fired central station power plants since the 1950’s. I don’t consider that accurate, as Integrated Gasification Combined Cycle (IGCC) seems like a dramatic improvement in the efficiency of the usage of coal for power production. Several of these IGCC plants will be coming online in the U.S. over the next decade, and a number have already been built in China. (You can see some of the plants that have been completed or are in progress around the world here).

There were some things I found annoying about the book. For instance, it had no graphs. However, on a number of occasions the author said “picture a graph in which the Y axis represents one variable, and the X axis another variable.” Why not just show a graph? Or if for some reason you are limited to no graphics, find another way to make the point.

There were some calculations that just didn’t make sense to me. For instance, she once calculated the required size of a PV system to run a household in Phoenix “if PV cells were 100% efficient.” Why not just do the actual calculation with typical PV efficiencies? She also commented that NREL had done a calculation in which they concluded that “100 square miles that constitute the Nevada Test Site” covered in PV arrays could meet the needs of the entire U.S. (without addressing storage). I did a similar calculation in which I tentatively came up with an area of about 100 miles by 100 miles. So I wonder if she didn’t mean that the NREL calculation concluded that a 100 mile square (10,000 square miles) would suffice.

She also spent a good deal of time talking about how a terrorist could bring down the transportation system or the electrical grid. I don’t think those are the kinds of ideas we want to plant in people’s heads.

One thing that isn’t clear to me is just how utilities benefit from efficiency improvements of their customers. She spent some time discussing various utility programs to improve the efficiency of the end user so they don’t have to construct new power plants. But utilities make their money selling electricity, don’t they? If customers improve efficiency, they just means they are selling less electricity to that customer. But there is apparently something to this model that I don’t fully understand, because I know that utilities are always pushing for – and even subsidizing – these sorts of programs. In Hawaii, the utility will pay for part of a solar hot water installation. So how do they benefit? Perhaps the utilities are compensated by various governments for pushing these efficiency programs. Otherwise, it seems that as consumers become more efficient, the utilities would have to charge more money for the electricity.

One other thing that was discussed – but that has always puzzled me – is the economic multiplier theory. She gave one example about how the benefits of a local Midwestern project ended up contributing three times the income generation to the local economy. Now I can see how a multiplier should work in theory. Pay a guy $100 in salary, and then he pays his taxes and turns around and spends that $100 in the local economy. That merchant then pays his taxes and spends some of it in the local economy, such that the initial $100 supports more than $100 in taxes and spending. In practice, it seems like if it really worked that way, we would subsidize everything. Why would we want to get any autos from Japan? Subsidize U.S. consumers for 50% of the cost of a domestic car, and then let the local multiplier give back 3-4 times that amount to the local community. But in reality, I don’t quite think it works out that way.

In summary, while it seems like I found a lot to nit-pick in the book, I did find a lot of useful information in there. Even the things I found puzzling caused me to think and to do additional research, which was helpful. The author spends a lot of time laying out the present situation with respect to electricity, and talking about the changes that need to happen. The author is peak oil aware, citing Matt Simmons and Tom Whipple (among others) with respect to a projected future energy crunch. I think the anti-nuclear stance was misguided, and I think she overestimates the ability of renewables to fill in for growing demand and the phase-out of older coal-fired power plants. In my view, it is hard to imagine how we are going to get by without building more nukes in the next few decades.

October 11, 2009 Posted by | book review, electricity, electricity usage, nuclear energy, solar power | 86 Comments

Notes on Energy Efficiency

I arrived in one piece in Hawaii a few days ago, and have been settling in. It is still hard to believe I am here, and I plan to elaborate a bit on why I am here in the near future.

In the interim – and because I haven’t posted anything new in a few days – I thought I would call attention to a story in the New York Times from a couple of days ago:

Energy Efficiency: Fact or Fiction?

You have to be registered to read it (although the Tehran Times has reprinted the first page of the article) but I will paraphrase/excerpt it. The article covers a number of facts and myths around energy efficiency:

COMPUTERS AND ELECTRONICS

1. Screen savers save energy

FICTION — With screen savers, electricity is still pumping to keep your computer and monitor running. In fact, screen savers may even use more energy than a basic blank screen.

2. Your computer stops using energy when in sleep mode

FICTION — Computers still use energy when in sleep mode, but about 70% less.

3. You waste more energy restarting a computer repeatedly than letting it run all day

FICTION — Even though a small surge of energy is required to start up a computer, this amount is less than the energy consumed when a computer runs for long periods of time.

MAJOR APPLIANCES

4. No energy is used after you turn appliances and electronics off

FICTION — Many appliances still draw a small amount of electricity when turned off. Solve this by plugging into a power strip that you can turn off.

5. It’s more efficient to keep your refrigerator full than half full

FACT — The larger the mass of cold items in a refrigerator or freezer, the less work is required to maintain the appliance’s chilly temperature. (Of course the more work it then takes to get the appliance to its chilly temperature).

6. Hand-washing dishes is more energy efficient than a dishwasher

FICTION — Dish washing by hand actually consumes more water and energy. People typically leave the hot water running, using up to 14 gallons of water on average. GE Appliances’ Paul Riley says to get the most out of an energy-efficient dishwasher, make sure it is fully loaded with food scraped off the plates.

7. Wash clothing with hot water for a truly effective wash.

FICTION — Heating the water for laundry makes up about 90 percent of the energy used in a conventional top-load washer. Using warm and cold water can be just as effective and can slash your energy use in half or more.

CARS AND FUEL

8. It’s better to fill your gas tank halfway because a full tank adds weight and is therefore less fuel efficient

FACT — The lighter your car, the better the fuel economy.

9. If you live in a warm climate, buy a light-colored car.

FACT — The lighter colors reflect the heat, whereas dark vehicles absorb heat and require more air conditioning to cool down.

AROUND THE HOUSE

10. If you live in a warm climate, paint your house a light color

FICTION — A light-colored roof helps dial back the temperature in a home’s attic by reflecting sunlight, but insulation is the key factor when it comes to energy savings. To really cool down your house, focus on proper insulation and plant foliage to block the sun’s rays.

11. Shut the door and vents in unused rooms

FACT — This works only if you close the doors and vents in multiple rooms.

12. Leave the heating or cooling system on all day. If you shut it down when you’re away, the system needs a surge of energy to reach the desired temperature.

FICTION — Switching the thermostat off when you go to sleep or leave for the day will boost energy savings. It will take more energy to bring your house back to the set temperature, but less energy is used during the down times. You can also realize substantial savings by changing the temperature settings. It is estimated that you will realize a 2 percent savings on your energy bill for every degree you cut back.

August 18, 2009 Posted by | electricity, electricity usage, fuel efficiency | 19 Comments

Running the Electric Grid with eSolar

As I often do on a Saturday morning, I was up early reading through energy headlines. I happened across this story on eSolar:

Bill Gross’s Solar Breakthrough

“We are producing the lowest cost solar electrons in the history of the world,” Bill Gross is telling me. “Nobody’s ever done it. Nobody’s close.”

“We have a cost-effective, no-subsidy solar power solution and it’s for sale, anywhere around the world,” he says.

The article was intriguing, and inevitably led me back to eSolar’s website to get a better idea of whether the claims appear to have merit. There, I watched the slide show on the technology, and caught this bit: A single unit generates 46 MW of clean electricity on a footprint of 160 acres.

While this doesn’t help me figure out whether they can deliver on the hype, it does enable me to update a couple of essays that I have written before:

A Solar Thought Experiment

Replacing Gasoline with Solar Power

In the first, I made an attempt to calculate the area that would be required to equal the entire installed electric capacity of the U.S. – using only solar power. (Yes, I understand that this number falls to zero at night). The numbers quoted above from eSolar – combined with the latest data on installed electrical generating capacity – enabled me to update that calculation.

Per the EIA, total installed electrical generating capacity in the U.S. is approximately 1 million megawatts. If we scale up eSolar’s claim of a required footprint of 160 acres to produce 46 MW of electricity, then it would require 5,435 square miles of eSolar technology to equal current U.S. electrical capacity. This is a square of 73.7 miles by 73.7 miles. This is greater than the 2,531 square miles calculated in the previous essay, but that essay only considered the area for solar panels. The present calculation encompasses the footprint of the plant.

Looking back at the gasoline calculation, I came up with 1,300 square miles required in my previous essay to replace the energy gasoline provides. Using the current eSolar numbers changes that number to 2,413 square miles, or a square of 49 miles on each side.

Of course all of the normal caveats apply as spelled out in the previous essays. The key point is not to read these sorts of thought experiments too literally. I tend to do them to get my head around the scale of certain problems. Complaints of “the cost is too great” or “the power is intermittent” – addressed by caveats in the previous essays – completely miss the point of the essay. It is sort of like trying to figure out how much biomass would be required to power the world. If the calculation is 10 times the current annual output of biomass, then that’s not going to work. If it is 1/100th the current annual output of biomass, then that might work (again, pending lots of other things working out).

In this case, I find this eSolar thought experiment encouraging insofar as the required land area isn’t a clear knockout.

August 8, 2009 Posted by | electricity, electricity usage, eSolar, solar efficiency, solar power, solar thermal | 29 Comments

Geothermal’s Earthquake Problem

In a recent post – It’s Always Something – I argued that for seemingly every renewable option, there is a trade-off. In that particular essay I was discussing a recent report that suggested that jatropha curcas – which I have written about as an intriguing option for renewable, liquid fuels – has very large water requirements. It is also poisonous, and was banned as an invasive species by the Western Australian State government. So as the title suggested, there always seems to be a catch with any of these options.

Geothermal energy is one of the most promising renewable energy technologies. There are a number of commercial geothermal plants already in operation (the U.S. is the world leader in geothermal energy), and the economics are much more favorable than some of the other choices. Geothermal electricity makes a much larger contribution to the electricity mix than does solar power, and does not suffer from the intermittency issue. A 2006 report from NREL (PDF warning) concluded that the potential for domestic geothermal energy at a depth of 2 miles (3 kilometers) is 30,000 times all current annual U.S. energy usage.

But while the current plants in operation utilize geothermal energy that is close to the surface, tapping deeper into the earth would hugely increase the geothermal potential. The only problem is that this sort of deep drilling can cause earthquakes. From the New York Times:

Deep in Bedrock, Clean Energy and Quake Fears

BASEL, Switzerland — Markus O. Häring, a former oilman, was a hero in this city of medieval cathedrals and intense environmental passion three years ago, all because he had drilled a hole three miles deep near the corner of Neuhaus Street and Shafer Lane. He was prospecting for a vast source of clean, renewable energy that seemed straight out of a Jules Verne novel: the heat simmering within the earth’s bedrock.

All seemed to be going well — until Dec. 8, 2006, when the project set off an earthquake, shaking and damaging buildings and terrifying many in a city that, as every schoolchild here learns, had been devastated exactly 650 years before by a quake that sent two steeples of the Münster Cathedral tumbling into the Rhine.

Hastily shut down, Mr. Häring’s project was soon forgotten by nearly everyone outside Switzerland. As early as this week, though, an American start-up company, AltaRock Energy*, will begin using nearly the same method to drill deep into ground laced with fault lines in an area two hours’ drive north of San Francisco.

The New York Times article goes into a lot of detail about why the deeper geothermal techniques cause earthquakes, but it also gives a good overview of the geothermal potential. I think the solution to this – if they can’t come up with techniques that don’t spawn earthquakes – is to only tap geothermal in relatively uninhabited locations. There are lots of places in the Western United States that have very low population densities, but very high geothermal potential.

Regardless, geothermal is one of those options that I think is around for the long haul, and won’t require endless subsidies in order to be competitive.

* As a footnote, AltaRock Energy is a company that Vinod Khosla has invested in. AltaRock also has some information at their site about how geothermal works.

June 27, 2009 Posted by | AltaRock, electricity, geothermal, Vinod Khosla | 50 Comments

Wood Gasification Plant Opens

Been really tied up, but saw this story yesterday and wanted to bring attention to it. I think it is significant, and a sign of things to come. Not much time to comment, but some excerpts from the article:

Plant making gas from wood opens in Austria

GUESSING, Austria (AFP) – A new plant that produces gas from wood was opened in Austria on Wednesday, paving the way towards new possibilities in renewable energy.

According to its backers, the gas produced at the plant can be used in urban heating systems, for gas-powered cars or by power stations that work on gas.

“The gas produced has the same quality as natural gas,” said Richard Zweiler, from the European Centre for Renewable Energy (EEE), which is behind the project.

A plant able to produce between 20 and 25 megawatts of power — about 25 times bigger than the Guessing project — is already in the works in Goteborg, Sweden.

Readers may know that I am a big fan of gasification over the long haul. Whether the approach described here turns out to be the right one or not, I think gasification makes far more sense than some of the renewable paths we have headed down. I believe 20 years from now we will be doing commercial biomass gasification for heat and power. I don’t believe we will be making commercial quantities of cellulosic ethanol or algal biofuels.

June 25, 2009 Posted by | biomass gasification, chp, electricity | 36 Comments

Detroit Gearing Up for Electric Cars

The Dodge Circuit Electric Vehicle

Regular readers know that I am hopeful that electric cars can start to become one of our transportation options in the next few years. There are several reasons for this. First and foremost, it is because there are so many different options for making electricity. We currently make it primarily from coal and nuclear power, but over time renewable electricity production is expected to grow sharply. The car performs the same way whether the electricity comes from coal, natural gas, wind, geothermal, or solar power.

The second major factor behind my desire to see us move toward electric transportation is that the efficiencies of electric motors are much higher than for gasoline engines. In an essay that I wrote last year, I linked to an analysis that showed that the overall efficiency of an electric vehicle is about double that of the internal combustion engine.

The final reason I favor a move toward electric vehicles is that it simply diversifies our transportation options. I want to see us develop expertise in that area, but also in the areas of improving diesel hybrids, CNG vehicles, etc. In an age of limited fossil fuel supplies, diversification provides more protection against supply disruptions.

Over the weekend, the New York Times published a story on the electric vehicles in the pipeline:

Detroit Goes for Electric Cars, but Will Drivers?

Some excerpts summarizing what we should expect:

DEARBORN, Mich. — Inside the Ford Motor Company, it was called Project M — to build a prototype of a totally electric, battery-powered car in just six months. When it was started last summer, the effort was considered a tall order by the small team of executives and engineers assigned to it. After all, the auto industry can take years to develop vehicles.

But Ford was feeling pressure from competitors, and decided it could not afford to fall behind in the rapidly expanding race to put electric cars in dealer showrooms. Ford plans to make only 10,000 of the electric vehicles a year at first — very few by Detroit standards — to test the market cautiously.

The competition over electrics is picking up speed and players. Toyota, which has so far focused its efforts on hybrid models, will display a battery-powered concept car at the Detroit show. Nissan’s chief executive, Carlos Ghosn, has promised to sell an electric car in the United States and Japan as early as next year.

Two Japanese automakers, Mitsubishi and Fuji Heavy Industries, the parent company of Subaru, are also testing electric cars. And Chrysler, the most troubled of Detroit’s three auto companies, has vowed to produce its first electric car by 2010.

Of course one of the major limitation is the energy density of the batteries, which by fossil fuel standards is quite low. However, the push by the auto industry has boosted investments into storage technologies:

The surge toward electric vehicles also appears to be jump-starting investments in advanced-battery production in the United States. General Motors will announce plans at the auto show to build a factory in the United States to assemble advanced batteries for its Chevrolet Volt model, which it expects to start selling next year.

Ultimately, though, whether consumers will embrace these vehicles will come down to cost and convenience. At the $40,000 price tag that was mentioned in the story for the Chevy Volt, consumers aren’t going to embrace them. There is also the matter of convenience. Ford indicates that it will take six hours to put a charge on that will give the vehicle a range of 100 miles. While that’s a pretty good range, what if I forget to plug my car in? Running out of gas is preferable to that. But as the article goes on to point out, the average American drives less than 35 miles a day, so even if I forgot to plug in overnight, I still have a 2nd (and maybe 3rd) chance to get the vehicle charged overnight.

We will always need liquid fuels, though, as long-haul trucking and airline transportation are well-suited for the high energy density of liquid fuels. Here’s hoping, though, that the electric vehicle can finally make some inroads.

January 12, 2009 Posted by | Chevy Volt, electric cars, electricity, Ford | 46 Comments

Detroit Gearing Up for Electric Cars

The Dodge Circuit Electric Vehicle

Regular readers know that I am hopeful that electric cars can start to become one of our transportation options in the next few years. There are several reasons for this. First and foremost, it is because there are so many different options for making electricity. We currently make it primarily from coal and nuclear power, but over time renewable electricity production is expected to grow sharply. The car performs the same way whether the electricity comes from coal, natural gas, wind, geothermal, or solar power.

The second major factor behind my desire to see us move toward electric transportation is that the efficiencies of electric motors are much higher than for gasoline engines. In an essay that I wrote last year, I linked to an analysis that showed that the overall efficiency of an electric vehicle is about double that of the internal combustion engine.

The final reason I favor a move toward electric vehicles is that it simply diversifies our transportation options. I want to see us develop expertise in that area, but also in the areas of improving diesel hybrids, CNG vehicles, etc. In an age of limited fossil fuel supplies, diversification provides more protection against supply disruptions.

Over the weekend, the New York Times published a story on the electric vehicles in the pipeline:

Detroit Goes for Electric Cars, but Will Drivers?

Some excerpts summarizing what we should expect:

DEARBORN, Mich. — Inside the Ford Motor Company, it was called Project M — to build a prototype of a totally electric, battery-powered car in just six months. When it was started last summer, the effort was considered a tall order by the small team of executives and engineers assigned to it. After all, the auto industry can take years to develop vehicles.

But Ford was feeling pressure from competitors, and decided it could not afford to fall behind in the rapidly expanding race to put electric cars in dealer showrooms. Ford plans to make only 10,000 of the electric vehicles a year at first — very few by Detroit standards — to test the market cautiously.

The competition over electrics is picking up speed and players. Toyota, which has so far focused its efforts on hybrid models, will display a battery-powered concept car at the Detroit show. Nissan’s chief executive, Carlos Ghosn, has promised to sell an electric car in the United States and Japan as early as next year.

Two Japanese automakers, Mitsubishi and Fuji Heavy Industries, the parent company of Subaru, are also testing electric cars. And Chrysler, the most troubled of Detroit’s three auto companies, has vowed to produce its first electric car by 2010.

Of course one of the major limitation is the energy density of the batteries, which by fossil fuel standards is quite low. However, the push by the auto industry has boosted investments into storage technologies:

The surge toward electric vehicles also appears to be jump-starting investments in advanced-battery production in the United States. General Motors will announce plans at the auto show to build a factory in the United States to assemble advanced batteries for its Chevrolet Volt model, which it expects to start selling next year.

Ultimately, though, whether consumers will embrace these vehicles will come down to cost and convenience. At the $40,000 price tag that was mentioned in the story for the Chevy Volt, consumers aren’t going to embrace them. There is also the matter of convenience. Ford indicates that it will take six hours to put a charge on that will give the vehicle a range of 100 miles. While that’s a pretty good range, what if I forget to plug my car in? Running out of gas is preferable to that. But as the article goes on to point out, the average American drives less than 35 miles a day, so even if I forgot to plug in overnight, I still have a 2nd (and maybe 3rd) chance to get the vehicle charged overnight.

We will always need liquid fuels, though, as long-haul trucking and airline transportation are well-suited for the high energy density of liquid fuels. Here’s hoping, though, that the electric vehicle can finally make some inroads.

January 12, 2009 Posted by | Chevy Volt, electric cars, electricity, Ford | 46 Comments

Replacing Gasoline with Solar Power

Executive Summary

If you don’t want to run through the calculations, here is the summary. I attempted a thought experiment in which I calculated whether it would be feasible to use solar power to generate enough energy to offset all U.S. gasoline consumption. My conclusion is that it will take about 444,000 megawatts of electrical generating capacity. Current U.S. generating capacity is over 900,000 megawatts, but there isn’t a whole lot of spare capacity in that number.

To generate 444,000 megawatts with solar PV would require just under 1,300 square miles (a 36 mile by 36 mile square) of just PV surface area. To generate that much power with solar thermal – including supporting infrastructure – would require 4,719 square miles (a 69 mile by 69 mile square). A large area, but not impossible to envision us eventually achieving this.

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Introduction

Having made an attempt to calculate the number of square miles to replace current U.S. electricity consumption via solar PV or solar thermal, I have been challenged to do the same exercise for replacing our gasoline usage. (In fact, I was told by someone that they had never seen this kind of calculation done, so I told them I would do it). I have no idea how this calculation is going to turn out, but I suspect it is going to be similar to the previous calculation for replacing electrical consumption. My guess is less than 100 miles by 100 miles. Note that this is a thought experiment, in which I try to get an idea of what it would take to achieve this.

First, some caveats. There are still technical obstacles that prevent this scenario from being realized. Those are, 1). Battery range is still too low (The plug-in Prius is only going to be able to go 7 miles on battery power).; and 2). Solar power can’t be adequately stored. However, that’s not the purpose of the exercise. The purpose is to satisfy my curiosity: If we were going to try to replace gasoline with solar power, are the land requirements prohibitive?

I am only going to do this calculation for gasoline, as I think it is unlikely that electricity will ever power long-haul trucks or airplanes.

How Much Do We Need?

The U.S. currently consumes 389 million gallons of gasoline per day. (Source: EIA). A gallon of gasoline contains about 115,000 BTUs. (Source: EPA). The energy content of this is equivalent to 45 trillion BTUs per day. The average efficiency of an internal combustion engine (ICE) – that is the percentage of those BTUs that actually go into moving the vehicle down the road – is about 15%. (Source: DOE). Therefore, the energy that goes toward actually moving the vehicles is 6.7 trillion BTUs per day.

The efficiency of electric infrastructure can be broken down into several steps. According to this source, the respective efficiencies for the transmission lines, charging, and the vehicle efficiency are 95%, 88%, and 88%, for an overall efficiency (after the electricity is produced) of 74%. To replace the gasoline BTUs that go toward moving the vehicle with electricity is going to require 6.7 trillion/0.74, or 9.1 trillion BTUs. To convert to electricity, we use 3,413 BTUs/kilowatt-hour (kWh). Thus, 9.1 trillion BTUs/day is equal to 2.7 billion kWh/day. That’s how much energy we need. To convert this to power, we need to multiply by 1 day/24 hours, and that gives us 111 million kilowatts, or 111,000 megawatts (MW) of power generation required.

Looking back at my Solar Thought Experiment, I calculated 2,531 square miles to replace our peak electrical demand of 746,470 MW (746 GW). However, the current calculation is a different sort of calculation than what I did previously. The previous calculation attempted to have enough installed solar PV to meet peak demand. In the case of replacing our transportation fuel, I need enough panels to produce the required transportation energy in 8 hours or so while the sun is shining. To be conservative, we can assume 6 hours, which means we will actually need four times the 111,000 MW, or 444,000 MW.

Using Solar PV

From the previous essay, I used a conservative value of 12.5 watts per square foot as the generating capacity of an actual GE PV panel. To get 444,000 MW is going to take an area of 35.5 billion square feet, which is 1274 square miles. This is an area of just under 36 miles by 36 miles. However, this is just the surface area required to generate the electricity. It does not include area required for supporting infrastructure.

Using Solar Thermal

Doing the same calculation based on the solar thermal output from Running the U.S. on Solar Power, the expectation was that 0.147 megawatts could be produced per acre. This did include all of the land associated with infrastructure. If we use that number, we find that to generate 444,000 MW is going to take a little over 3 million acres, or 4,719 square miles. This is a square of just under 69 miles by 69 miles.

The reality is that we would use a combination of the solar PV and solar thermal. We have a lot of available rooftops that can create electricity with solar PV, and there are large tracts of land in sunny Arizona and Nevada that can create electricity with solar thermal.

Conclusions

Clearly, a lot of area is required, but it isn’t impossibly large. Of course to achieve this, a couple of big problems need to be resolved. First, battery life needs to improve somewhat before people are going to embrace electric transport. According to this ABC News story, the average commute is 16 miles one-way, but the range of the plug-in Prius is only expected to be 7 miles. The Aptera, on the other hand, claims a range of 120 miles. Maybe we just need to change the way we think about what we drive. (On the other hand, not a lot of commuters are going to climb into an Aptera if they have to share the road with large SUVs).

Second, and the bigger issue, is that we still don’t have a good way to store excess solar power. We need to have a good storage mechanism so electric cars can be charged at night from solar electricity produced during the day. One idea for this that I have seen floated is to use peak solar energy to electrolyze water, and then store the hydrogen in centralized locations. The hydrogen would then be burned at night to run centralized electrical generators. Not the most efficient method for storing solar energy, but technically workable.

Finally, the current electrical grid couldn’t handle such a large increase, but the model I envision would generate and consume the electricity locally.

Note

I had delayed posting this for almost a week, because I was sure there was an error in the calculations. I finally found one (I had turned a kilowatt into a watt), but let me know if you find other errors or incorrect assumptions.

May 12, 2008 Posted by | electric cars, electricity, electricity usage, solar power, solar PV, solar thermal | 107 Comments