Friday, August 03, 2007

Is A Carbon-Free and Nuclear-Free Future Reasonable?

The Institute for Energy and Environmental Research (IEER) and the Nuclear Policy Research Institute (Dr. Helen Caldicott’s organization) just released an Executive Summary of Carbon-Free and Nuclear-Free: A Roadmap for U.S. Energy Policy. It is a book that will be published in October 2007 detailing recommendations on how the U.S.’ can meet future energy demand while reducing carbon emissions.

The joint project sets out to answer three questions:

Is it possible to physically eliminate CO2 emissions from the U.S. energy sector without resort to nuclear power, which has serious security and other vulnerabilities?

Is a zero-CO2 economy possible without purchasing offsets from other countries – that is, without purchasing from other countries the right to continue emitting CO2 in the United States?

Is it possible to accomplish the above at reasonable cost?

My answers are yes, yes and no.

To the first question, it is possible to eliminate CO2 and nuclear from the energy sector -- all we need to do is quit consuming energy. With current technology, there is no way CO2 and nuclear will be eliminated at the same time. It will have to be one or the other. The executive summary, however, suggests otherwise. More further down.

To the second question, why would we purchase offsets from other countries in the first place? The goal is to reduce and stop emitting carbon. We shouldn’t need to justify emitting CO2 by purchasing offsets. Just do it.

The third: Is it possible to accomplish the above at a reasonable cost? I guess that depends on your definition of reasonable. Does reasonable mean doubling or tripling electricity prices? According to the solutions presented, I don’t believe reasonable is even close to what's actually practicable.

How Much?
Figure 2 on page 9 of the summary details how the electric grid will be configured by 2050 without coal or nuclear power. Solar PV and solar thermal are assumed to generate 40-45% of the electricity supply. Since solar is the fuel source to provide the most electricity, let’s start out by determining how much solar would be needed to provide 40-45% at today’s demand (to keep it simple).

In 2006, total U.S. electricity net generation was 4,053 bkWh. Forty five percent of this is 1,824 bkWh. In 2006, solar generation was only 0.5 bkWh with a total capacity of 0.4 GW and a capacity factor of 19%.

If solar is to provide 1,824 bkWh to meet today’s demands it would need 1,095 GW (1,824,000 mkWh / (8,760 hours in a year * 19% capacity factor) = 1,095 GW). Total U.S. electrical generating capacity is nearing 1,000 GW.

So we would need to build more solar capacity than the total current capacity of all the generating capacity in the U.S. just to provide less than half the electricity at today’s levels!

The demand by 2050 could be twice as much.

Taking aside growth in electricity demand, let us calculate what 1,095 GW of solar would mean. We have about 42 years left until 2050 which means the U.S. will need to build roughly 26 GW of solar each year or 2 GW each month or 1 GW every two weeks. And this is just for the U.S.

A 2006 document from IEER (p. 2, pdf) states that nuclear would need to build 2,500 GW worldwide to help with CO2 emissions which would have to be built “more rapid than one a week.” Of course IEER believes this is impossible for nuclear but for solar to make a dent we know it would have to be more worldwide under IEER’s scenario.

What’s interesting about the executive summary is it hasn't so far shown how much capacity would be needed from any of their alternatives. You would think that would be the first data presented as IEER always points to it for nuclear, but it is not. Hopefully the book will provide a quantitative analysis of this sort.

My little exercise actually applies to all fuels including nuclear so I don’t want it to sound like I’m picking on solar. But since the book’s main supply of electricity is solar then we of course need to analyze its task ahead. In reality, these calculations will always come out to show that a lot of everything will be needed to mitigate climate change because a lot of everything will be needed just to meet new demand.

Cost
If the reader looks at Table 2 on page 17 of the study, they will find that IEER’s reference scenario by 2050 is projected to be cheaper to the consumer then the business as usual scenario. Considering that solar right now is the most expensive technology (Table 39, p. 77, pdf) and it is a main crux to IEER’s electricity supply, we need some major, major cost breakthroughs with solar to occur if that is to happen. I'm very interested to see how the project calculated this scenario because the assumptions are very optimistic to say the least.

If the reader moves to page 18, they will find a table listing all the technologies included in the project's plan. When I look at the table, I see many of the solutions still in the R&D stage, a few demonstration plants needing more development and major cost reductions required before full scale commercial implementation can happen. Reads like a wish list to me.

Well let me throw out some stats of another source which is readily available, proven and is already making a dent in carbon reductions. Nuclear power in the U.S. was the largest source of emission free electricity in 2006. Nuclear power in the U.S. avoided 682 million metric tons of CO2 in 2006. Worldwide nuclear energy avoids on average the emissions of more than 2 billion metric tons of carbon dioxide per year. And, U.S. nuclear plants comprise only 10% of the U.S. generating capacity, yet provide 19% of its electricity. Funny how these stats don't matter in reports against nuclear.

I'm getting ahead of myself of course because I'm sure there are some great ideas in the book to consider. So I'll hold off final remarks until it is released. Stay tuned.

13 comments:

bvidalin said...

I believe we should give a fair test to Dr. Makhijani's hypothesis on solar at a "reasonable cost". Would someone out there please built me a solar plant with a bus-bar cost of 1.75 cents/Kw-hr? Oooops, that's the average for nuclear. How about if he just stays under 10 cents/Kw-hr? The best us engineers can do with PV is 40 cents/Kw-hr, but we haven't read his book yet...

Anonymous said...

"many of the solutions still in the R&D stage, a few demonstration plants needing more development and major cost reductions required before full scale commercial implementation can happen. Reads like a wish list to me."

It also precisely describes DOE's plans for the Global Nuclear Energy Partnership or Next-Generation Nuclear Plant.

CandyMan Sha Bam said...

The largest solar farm yet, at 640 acres, is being constructed in California. It will produce 80MW. That's about 1/8th MW per acre. At that rate, 1,095 GW solar capacity would cover 8,760,000 acres. If we converted the whole of the state of Maryland (7,940,000 acres) into a solar farm, we still would not have enough capacity to meet demand. This is assuming the rest of the country has as many cloud-free days as the San Joaquin valley.

Mike Oliver said...

Solar elctricity is a hoax, worthyh\ of the worst shyters the world has ever seen. Solar electricity has been promised for decades by the green extremist leftists, and always brought us the same result because of a factor known was energy density. Solar will requrie about 50 times the material per kilowatt-hour of electricity than nuclear -- which is why no nation anywerhe on earth is using solar for elctricity to any significant extent. This incluses Israel. With all its sunshine 80% of its water us heated with solar panels, but less than half a percet produces electricity. Not that its own greens aren't pushing solar electricity to the highest extent. Its greens are as corrupeted as ours are.

I won't go into details on tis, but let the reader do his/her own calculations.

Luke said...

I've been awaiting this publication for some time.

Let's see if they can put up a realistic case. If they can't, we'll call them on it.

Luke said...

Ignoring the growth in electricity demand, to build 1095 GW of solar by 2050 the U.S. would need to build roughly 26 GW of solar capacity each year or 2 GW each month or 1 GW every two weeks.

If this is all from photovoltaic cells, and assuming you can get, say, 150W per square meter of photovoltaics, you have to build... 3.33 square kilometres of photovoltaic panels per week.

And you've got to mine the Silicon, you've got to refine Silicon to 99.9%, and you've got to grow the crystals for these photovoltaic devices, and you've got to dope the Silicon, with Boron, Arsenic, Phosphorus, toxic things like this, and you've got to etch it with lethal hydrofluoric acid, and all these stages require energy inputs, clearly being supplied by coal-fired plants, right? Phew, I'm running out of breath, I don't know how Helen does it.

Compare that with the 1 reactor per week which is the figure they are quick to trump out for 2500 GW of new nuclear capacity worldwide by 2050 in order to make a difference (for some value of a large difference) to carbon emissions.

Let's say it takes four years to plan, build and set up a reactor. Building one at a time, we could build 10 over the next 40 years.

Given that we could reactivate mothballed reactors, get more capacity out of existing reactors, and get more than 1 GW from a single new reactor, then we perhaps need to build 200 reactors at once, throughout the entire world. Seems practical.

Daniel said...

I'm willing to suggest a way to cut your solar power cost by ~10% over whatever it currently is. I can do this with a different design of the solar panel which uses 1/3 fewer solar cells. Design is patent pending FWIW.

David Wogan said...

Great find. I posted some thoughts over at my site. Take a look if you'd like. Keep up the great work.

David
www.davidwogan.us

Anonymous said...

There's a fundamental flaw in the assumptions of all those so gleefully bashing solar PV: that it must be a GW-scale, centralized plant like nuclear.

These things can go on roofs of individual home and business owners. There's nothing about electricity generation that inherently requires it to be done at large, centralized, 1,000-MW plants.

Also, silicon's not the only material that can used for solar PV these days. That's like indicting nuclear power based on its 1950s technology base.

KenG said...

Anonymous is right in that PV can be done on a small scale. However, the same limitations exist. The availability is low and unpredictable. It still requires a "spinning reserve" for system availability. The economic model that allows individual installers to sell back excess power at retail works when the PV power is insignificant but will fail if solar becomes a significant portion of the generation because there is no financial basis for maintaining the distribution system at that point.

Luke said...

Yes, we have better photovoltaic technologies in the pipepine today, that are far cheaper to build, a bit more efficient, and so forth.

But how mature are these technologies? We really need to have technologies that can be rolled out now on quite a large scale.

Society still uses the same amount of energy irrespective of it coming from small distributed generation capacity, or large centralised capacity, ignoring a very small factor due to transmission loss.

You can build an advanced photovoltaic with enormous quantum efficiency - it still doesn't work in the dark.

We often hear the ideas for large-scale pumped hydroelectric storage and so forth, but are there practical alternatives for smaller-scale energy storage systems for the home?

We're gonna need something better than a basement full of Lead-acid cells.

Ultimately, essentially the same amount of cells are still needed, if you have centralised or decentralised capacity.

Even the best solar cells, at present, do not have efficiency even close to that of Carnot cycles - and the energy wasted in a PV cell cannot be recovered via cogeneration or combined cycles.

Anonymous said...

Storage systems have limited capacity. Even if more efficient batteries, for example, were available for domestic PV, they have a limit for energy storage. Where I live there are periods where we seem to go for weeks without a peek of (direct) sunlight. Under those conditions, the PV array would be operating at limited efficiency during the day, zero at night, and so you'd be continuously drawing down whatever storage you managed to accumulate during sunny days. Eventually you'd run out, and then where do you turn? I would not want my family to be in a situation of having no electricity during a cold midwestern winter. Lives would be needlessly lost.

Anonymous said...

Could you please tell us more about yourselves, nuclear power advocates?
Do you live in the Southeast (U.S.)? Who hires you so that you can pay your power bill?

Thank you.

Bobbie