Tuesday, August 31, 2010

Solar and Nuclear: Economics and Land Use

Today, I am pleased to host this guest blog written by Willem Post.

Willem Post, Bob Hargraves, Howard Shaffer, Peter Roth, Steve Fox and I are all members of the local group, Coalition for Energy Solutions. Willem has both an MS in Mechanical Engineering and an MBA. He has many years of experience in financial estimation and oversight of large energy projects. Willem has written several reports on energy subjects. The Coalition For Energy Solutions Research and Reports page includes links to these reports. This is his first guest post for Yes Vermont Yankee.


A recent article on the New York Times Greenwire describes the Blythe Solar Power Project, BSPP. BSPP is a 968 MW thermal solar plant on 7,025 acres, or 11 square miles, of Bureau of Land Management, BLM, land in the California desert. The plant consists of (4) 242 MW units. Expected total energy delivered to the grid is 2,200 GWh. The capital cost will be $6 billion. It will take at least 6 years to complete. (A more complete description can be found in the project application documents.)

The BSPP will utilize solar parabolic troughs to generate electricity. Arrays of parabolic mirrors collect heat energy from the sun and refocus the radiation on a receiver tube located at the focal point of the parabola. A synthetic hydrocarbon is used as a heat transfer fluid (HTF). The HTF attains high temperatures (750 degrees F) as it is piped through the receiver tubes. The HTF is then piped through a series of heat exchangers where it releases stored heat to generate high- pressure steam. The steam is fed to a traditional steam turbine generator where electricity is produced. The plant is started in the morning and shut down in the evening.

Power Production

The annual production from the plant will be = 968 MW x 8,760 hrs/y x CF 0.26 = 2,200 GWh. The power varies daily and seasonally with the strength of the sun and is available only during the sunshine hours of the day.

For reference: Vermont uses about 6,000 GWh/yr

The NYTimes article states this power is enough for roughly 800,000 households. As a California household uses about 6,000 kWh/yr, about 4,800,000,000 kWh/yr would be required by these households.

The NYTimes statement is grossly inaccurate, unless the writer meant that the power is enough only during the sunshine hours of the day. This is a sizable difference of 2,600,000,000 kWh. For a NYTimes writer to report on thermal power and not understand the real world and the numbers is truly incredible.

Other power sources, such as pumped storage hydro, nuclear, wind, stored biogas (CO2 emitting) and fossil (CO2 emitting) will be needed to supply the 2,600,000,000 kWh during low-sun and sunless hours.

Note: Wind power also varies daily and seasonally with the strength of the wind, and is not available at all when wind strength is too little or too much.

As such variable power becomes a greater percentage of the power mix, one approach is to have a greater capacity of CO2-emitting spinning reserves. These are usually fossil power plants that are running without sending power to the grid, but they can be called on to instantly increase their outputs when required. Spinning reserves allow the grid to maintain its required steady voltage. If there is too much voltage variation, all sorts of electrical equipment will automatically shut down.

Environmental Effects of the Project

The land will be leveled by bulldozers to accommodate the arrays. Even though it is desert, no fauna and flora lives there?

The 11 square miles of surface will create a heat island in the desert, hotter than an equivalent desert surface that is partially covered with vegetation, as in New Mexico. Some of that heat will be radiated outwards and some of that will be reflected back. A new, hotter eco-balance will be created in that area. Building a large number of such plants will add to global warming. It runs counter to having white roofs on buildings to reduce the heat island effect and global warming.

Legislative Requirements and Tax Credits

The force that drives this project is California's renewables mandate for utilities and the 30% federal tax credit; about $2 billion in this case.

If a developer cannot use the tax credit, he can opt to get a check for $2 billion from the federal government. In other words, a check from all of us.

Thermal Solar Compared with Nuclear Power

A standard 1,000 MW nuclear plant for about the same cost as the above thermal solar plant would produce = 1,000,000 kW x 8,760 hrs/yr x CF 0.90 = 7,884,000,000 kWh/yr, 3.58 times the power of thermal solar plant.

This power is steady and 24/7/365, i.e., it is available during all hours of the day, CO2-free, and will serve ALL the power needs of 1,314,000 California households for a year.

New nuclear plants are designed to have useful service lives of about 60 years. A spreadsheet comparison of the lifetime costs of PV solar and nuclear plants would need to include the replacement of all PV panels and disposal of the old PV panels at a multi-billion dollar capital cost around the 25th year of the comparison.

The 1,000 MW nuclear plant would require about 100 acres. This is only 1.5% of the land area required for the 1,000 MW PV solar plant.

Given the above, it is to be expected that the smart and knowledgeable power industry experts in at least 30 major nations, such as the US, the UK, France, Germany, Sweden, Japan, China (building about 50% of the nuclear plants being built), India, etc., have convinced their governments to continue to opt for nuclear power as a major component of their future power mix.

To do otherwise is a folly.

A German Renewable Power Demonstration

Several German power industry experts created, for demonstration purposes, a “renewables utility company” that uses several field-mounted, sun-tracking PV solar plants in southern Germany, several wind farms in northern Germany, several biogas-fueled combined cycle gas turbine plants with biogas storage tanks and several pumped storage hydro plants, all controlled from a central point to maintain a nearly constant output to the grid, as would any traditional utility company.

The experts maintain that as it was shown to be technically feasable for a small combination of renewable power plants, it will be for increasingly larger combinations as well.

This works in Germany because its national grid is designed as their cars and trains. For this to work in the US, its national grid, with about 1,000,000 MW of power plants connected to it, will need to be rebuilt at a cost in the order of $200-$300 billion during the next 10-15 years. Going “variable and renewable” has its costs.

As an alternative, that level of funding could be used to replace 33,000-50,000 MW of the older US nuclear plants; no significant changes to the grid would be required.


martin Burkle said...

A nuclear plant could be located in a 100 acre plot but most are not. Here is a web site that tells the actual size of many of our nuclear reactor sites. Many of these sites are several thousand acres. http://www.eia.doe.gov/cneaf/nuclear/page/at_a_glance/reactors/nuke1.html
What are the current NRC rules for new nuclear reactor sites including radiation buffer and security requirements?

Willem Post said...

You are right. Site areas range from 34 ha (84 acres) for the San Onofre Nuclear Generating Station in California to 12,000 ha (30,000 acres) for the McGuire Nuclear Station in North Carolina.

As shown in table below, 28 site areas range from 200 to 400 ha (500 to 1000 acres), and an additional 12 sites are in the 400- to 800-ha (1000- to 2000-acre) range.

Thus, almost 60 percent of the plant sites encompass 200 to 800 ha (500 to 2000 acres).

Larger land-use areas are associated with plant cooling systems that include reservoirs, artificial lakes, and buffer areas.


Bill Young said...

The Willem Post article is not up to the usual editorial integrity of YVY. Specious arguments are being used and it detracts from otherwise valid points.

A concentrating solar plant does not need spinning reserves. A concentrating solar plant does not need to have its photovoltaic panels replaced.

It adds nothing to argue against a concentrating solar plant by using flaws of wind and PV generation.


Anonymous said...

I'm skeptical of the claim that large amounts of solar plants would contribute significantly to global warming due to increased solar absorption. Analyses basically show that dumping CO2 into the environment causes global warming; dumping heat into the environment does not (significantly).

Note that anti-nukes have been trying to use this argument against nuclear plants. After all, nukes do release a large amount of heat into the environment (being very large plants with a ~33% thermal efficiency). They've been trying to say that nuclear is therefore a significant contributor to global warming. This is frustrating given that the analyses show that such thermal releases have no significant impact.

If we get overzealous and try to throw in every plausible negative argument we've ever heard against solar (regardless of merit), we may lose credibility, or worse, the same arguments can be used against us.

Finally, while I understand that we need to confront the notion that renewables can meet all or most of our future needs, it is unhelpful to come across as being against/not-open-to/dismissive-of renewables. This will not win us support among many on the fence. A better story is for us to say we support both, and advocate a combiniation. We should be supportive of solar, in particular, since its generation profile (that shaves the daily) peaks dovetails particularly well with baseload nuclear . (Wind, on the other hand....)

Jim Hopf

Martin Burkle said...

Thank you Mr Post. So water cooling is really the determining factor to the land needed for a nuclear reactor.
That makes me wonder how one would cool the water after powering a turbine located in a desert when the temperature reaches 110. These desert solar concentrators must have some innovative cooling equipment!

Willem Post said...

Nuclear plants usually are located near large bodies of water. Some, such as VY, have cooling towers as well for when the Connecticut River level is low to avoid overheating the river.

The thermal solar BSPP in the California desert is air-cooled. This is quite common in the Middle East as well.

Willem Post said...

Bill Young,
The output of a thermal solar plant varies during the day.

The German experiment showed that by combining various renewable power sources and controlling them from a single command/control center, the combined system of plants can have a load following output similar to any other power utility.

My point is that the US grid and the lack of suitable renewable power sources prevent a repeat of the German experiment and that therefore other means are required to integrate variable/intermittent power into the grid.

I have been writing about PV solar so much that this item inadvertently entered into the text.

My intent is not to knock any power source, because all of them will be needed to play a role in the future; that includes nuclear, solar, biogas and natural gas fired CCGTs, wind, pumped-storage hydro, etc. Some power sources are more cost-effective than others.

Spain and Portugal have progressed more than most other nations towards using renewables.

Anonymous said...

New York City is an urban heat island that affects the local climate.

My point is the thermal solar plants in the desert will be desert heat islands.

Some people have suggested we have white roofs on our houses to lessen the urban heat island effect.

Some of our actions increase the heat island effect, others reduce it.

Charles Bell said...

Basic thermodynamics explains the local heat rise in the area of a very large solar array. Solar cells have low efficiency. They convert only a part of the electromagnetic energy they receive from the sun and re-emit the rest in infrared, which heats the surrounding air and will in fact raise the local temperature. This was one of the main drawbacks predicted in the early 1970s. I distinctly remember all this from the Energy sources physics course I took as an undergraduate physics major. The larger the area of these solar farms, the larger the impact to the local environment. The impact could be reduced by removing the rejected heat in the air above the solar arrays like power plants do now. That would further increase the cost of operation. I remember some basic back of the envelope calculations for 1973 that to power the U.S. energy needs, you would have to cover the state of Arizona with solar cells, but it would raise the local temperatures above 130 degrees F (assuming there was no air cooling)

Meredith Angwin said...

Hi everyone. It is great to have so many comments!

I just wanted to reply a little to Bill Young. The good news is I like the idea that Yes Vermont Yankee has a good level of editorial integrity. Thank you! The bad news is that you felt this post wasn't up to snuff.

I rarely have guest bloggers, but when I do have them, I don't edit very much beyond some grammar checks. It's their blog post, not mine. I read an earlier version of this essay, and I felt that Wllem had something important to say. So I invited him to guest blog.

That said, I should have edited this post a little more. I knew that in an earlier draft of this essay, Willem had been under the impression that the installation was PV, not concentrating solar. He changed the essay, but there were random leftovers such as his comments on solar panels. It's hard to edit your own work, so there is an excuse for him to have missed fixing this. There is no excuse for me to have missed pointing it out to him. My fault, and I apologize.

Thank you all for the comments.

donb said...

The problem with solar energy plants is once again illustrated with the figures given in the article. The average power delivered by the plant is 968 MW × 0.26 (capacity factor from article) = 261.7 MW. The installation covers 7025 acres. At 4840 square yards per acre, this is 7025×4840=34,001,000 square yards. The power in sunlight is roughly 1 kW per square yard (overhead sun). So at peak, the installation is intercepting 34,001 MW of solar energy. But it delivers only 261.7 MW. This means that it delivers an AVERAGE POWER equal to only 0.75% of the PEAK POWER that it intercepts! This follows from the intermittant nature of sunlight (0.26 factor), plus conversion efficiency.

To make things worse, the power being intercepted is diffuse, about only 1 kW per square yard. This means that very large structures are needed to gather it all in. A lot of work and material for a comparitively small amount of energy!

Joffan said...

I was interested to see the cost and build time of this large solar thermal project. $6 billion and 6 years. Not too dissimilar to build times for a nuclear plant, except that nuclear would be on around the clock.

I shall keep this one for the next too expensive/too slow argument.

Kit P said...

The purpose of solar is to make look nukes look good.

Based on the best solar project so far it, will take 485 years to build projects to produce the same amount of electricity. That is with the very generous assumption that solar works as intended. Since the O&M is more than value of electric, once something expensive break then they stop making electricity. Solar still continues to meet its original purpose. Pretty PR pictures.

I have yet to read one story of solar having delays and cost over runs. For the same reason , we do not hear stories about good performance. NEI brags about the performance of nukes but the solar industry rarely talks about electricity generation.

Say you want to build a new nuke. Step one build a solar project on the future site. Step two, start plotting kwh generated compared to the 40 year old nuke that might be replaced when the new one comes on line. I say might because a 60 year old nuke might become a 80 year old nuke.

Anonymous said...

I was told that Vermont Yankee contributes only 1% of Vermont's total energy consumption. The rest supposedly (99%) is exported. I find this hard to believe
I do not support the closing of Vermont Yankee, thinking there is no renewable energy source that is presently available to replace it.

This argument was made by a politician who favors closing Yankee.

Anonymous said...

Claims that Vermont Yankee only provides 1 percent of Vermont's total energy requirements has been made by some politicians that want it closed. I find this is hard to believe. Can any of you verify this?

Meredith Angwin said...

Vermont Yankee contributes about 1/3 of Vermont's electricity consumption. It exports the remaining 2/3 to neighboring states. It sits right on the river, and the other side of the river is New Hampshire. It is also very near the Massachusetts border. There are line losses in shipping electricity, so VY wouldn't be shipping power to the Northeast Kingdom. The power goes to nearby portions of the grid: Southern VT, Southern NH, Northern MA.

Politicians have their ways of....spin. For example, you will hear that VY is only "some tiny" amount of the grid capacity. However, the grid has a lot of capacity that consists of expensive plants, and these are turned on only on the hottest days. VY is a major portion of the actual power the grid PRODUCES. If shuts down, the ISO thinks that the area VY serves will not have a reliable power supply. (See my post of a few days ago).

Or a politician will throw all of Vermont's ENERGY use (transportation, home heating) into the mix, instead of making an apples-to-apples comparison of electricity sources.

Maybe I should write a book called "how politicians lie with energy statistics."

The bottom line is you are quite correct to be in favor of continued operation of Vermont Yankee.

dwbd said...

How much of the energy is supplied by the Natural Gas, backup (preheat & heat during cloud cover)?

It says Air Pollutants reductions are 85% of NG power plants. Is that 85% less than NG or 15% less than CCGT, OCGT.

Also it is not correct to say that the Solar Power supplies the daily peak power consumption. It will only supply about the 1st half of daily peak/shoulder load. To supply the 2nd half properly requires a battery backup system which will approximately double the cost from $24k per kwavg to $48k per kwavg. You can buy the latest - most highest tech machine ever built - the Virginia Class Nuclear submarine - for $2B with a 50 MW nuclear reactor with 33 yrs refuel cycle. 5 yr build time - start to finish. That's $40k per kw.

Anonymous said...

Why would Vermont build a Nuclear Power plant with the purpose of providing only 1/3 of it's energy to Vermont and 2/3s elsewhere?

The comment that Vt does not ship VT Yankee's power throughout the staten because of transmission costs does not make sense. Does Vermont not get a good deal of it's electricity from Quebec's Hudson Bay power
grid? That would seem to be a more significant transmission distance.

Where does the other 2/3 of Vermont's electricity come from?

Meredith Angwin said...

Good question. Basically, Vermont gets 1/3 from Yankee, 1/3 from Hydro Quebec, and 1/3 from other sources, which includes in-state hydro, a small amount from biomass, and fossil fuels. Here's a good link.
McNeil power is biomass, but it is co-fired with natural gas. Rod Adams has a good blog post on McNeil.

About line losses. Vermont is right up against Canada, and the north country actually uses the HQ power. Other places that buy HQ power may be actually using Yankee power...they buy from HQ, but the electricity comes from nearby. In the north, a utility may buy from Yankee but is actually use power from HQ. I know, it's confusing. It's just that people want to minimize line loss and maximize profits (sale price) and so you get this mix.

You ask why Vermont would build a plant which supplies other states. Plants are not built by states, usually. They are built by utilities or merchant generators (free agent utilities). Plants are part of a grid, and the question is "does this region need power." Also (minimize line loss, maximize profits), HQ prefers to sell high to Vermont and keep prices low at home. France prefers to sell high to Germany and keep prices low at home. I suspect that VY sells higher to a deregulated utility in MA than it sells in its home state. I don't know about VYs contracts actually, but this is my best guess.

I am getting a little out of my knowledge base here, though. I do know that most of HQ's profits come from its export sales. That is on the HQ website somewhere.

Rod Adams said...

In 2008, the Vermont Yankee Nuclear Power plant produced 4,895 GWhrs of electricity. The state of Vermont used 6,000 GWhrs.

However, like most commodities bought and sold in the United States, we have a national market where state borders are essentially invisible to the commodity.

(There are some exceptions in electricity - like Texas - but the Congress has the power to regulate interstate commerce, not the states.)

Due to some unique history, VY had a contract to sell about 1/3 of its capacity to the utilities inside Vermont at an extremely favorable rate of just 4.1 cents per kilowatt hour. That contract was part of the Entergy purchase deal, but the contract expires at the same time that the operating license was due to expire.

In my view, much of what is going on in Vermont is just a brinkmanship battle over prices. I am almost of a mind to recommend that Entergy call the bluff, shut down the plant to a cold standby condition and wait for people to start demonstrating at the gate for them to start the plant back up again.

Rod Adams said...

@donb - interesting comparison. Of course, there is a lot more to a VA class submarine that just a power plant. It comes complete with beds, sanitation and kitchen supplies for about 120 people! (Then there is that peace keeping component that is sort of the point of the investment.)

Willem Post said...

ISO-NE grid consumption = 130,000 GWh/yr
Vermont consumption = 6,000 GWh/yr
Vermont Yankee, VY, production = 620 MW x 8,760 hr/yr x capacity factor 0.90 = 4,888 GWh/yr. About one third is sold to Vermont utilities under long term contracts, the rest, most of it also under long term contracts, is mostly sold to other NE states.

VY supplies 4,888/130,000 x 100% = 3.76% of the ISO-NE grid.

Next time you hear a politician talk, mention these numbers

Also mention that VY power is STEADY, 24/7/365 and CO2-free, whereas wind and solar power are intermittent, variable, not there at all on cloudy days and at night and when there is too little wind and too much wind.

Without economically viable, large capacity power storage facilities (which have not been invented yet), wind and solar power cannot be used by most existing grids in percentages greater than about 5% of the total supply.

Portugal, Spain and Denmark, with wind consumptions of about 15%, 12% and 9% , respectively, use pumped storage hydro plants to smooth their wind power. In case of Denmark the hydro plants are Norwegian and Swedish.

Denmark PRODUCES about 20% of its power from wind, but exports 11% to Norway and Sweden and uses the other 9%.

Germany, with an excellent grid, but very little useful hydro plant capacity, is struggling with integrating 6% wind.

Anonymous said...

Hi again

I prefer not to be anonymous -- My name is John Earl and I live in Tunbridge, VT

I suspect that Vermont does not get the profits from the money made by Yankee---but it does probably get considerable taxes, and good paying jobs. Vt Yankee appears to have a bad maintenance track record that needs to be closely scrutinized. State appointed engineers need to be provided at the plants expense to monitor Yankee.

I am not totally comfortable with having a poorly maintained Nuclear power plant running for the next 20 years. I would love to have a CoGen plant that would, with appropriate scrubbers and filters, consume all the garbage, plastic and junk we use and toss in landfills.

How significant are the problems one reads about at Yankee?

Meredith Angwin said...

John. Thank you for your question. It is a good one and a big one and I don't know if I am fully qualified to answer it. I will try.

Vermont Yankee is a basically well-run plant. It's a shame you can't take a tour. It isn't an old falling-apart rust bucket. Many coal-fired power plants work for many more years than Vermont Yankee has operated. The coal plant in Washington D C started in 1952, the Merrimack plant in NH in 1968. As a former corrosion engineer, I can say that all steam plants need maintenance. Some parts of a nuclear plant are exposed to neutrons, some parts of a coal plant are exposed to particle impingement. Every type of plant has potential problems. This keeps corrosion engineers in business!

I can say some important things about VY safety and reliability. VY has a high NRC rating. VY did an amazing breaker-to-breaker run (which is how power plant people judge their plant's reliability and fitness). But, people won't necessarily believe me about any of it. Opponents answer that the NRC is in bed with the industry, the run means nothing, etc etc. People believe only the facts they want to believe, and explain away the rest.

This answer is getting awfully long. Let me just conclude by saying a garbage-burning plant won't do it. VY is a 600 MW plant. Merrimack is about the same. Merrimack burns about 40 100-ton coal cars a day. There's not that much garbage in Vermont.

About how significant are the problems? I don't think the problems are significant, but that can sound like a dismissal of your question. I want to answer, but I need to know which problems concern you. Can you email me at mjangwin at gmail? I will try to do a post on these issues in a few days.

My heavens. You wrote me during the Tunbridge Fair! Hey, everyone reading this. Think about going to the Tunbridge World's Fair this weekend!
It gets better every year, and it started in 1867.