Guest essay by Chris Yakymyshyn
Vermonter Bill McKibben was recently quoted in Salon Magazine:
“The roof of my house is covered in solar panels. When I’m home, I’m a pretty green fellow. But I know that that’s not actually going to solve the problem.”
This is a very interesting comment. He had solar panels installed on his home, even though he knew it would not ‘solve’ the CO2 problem.
One goal of installing solar PV is to reduce CO2 emissions associated with generating electricity. Ideally, this would be achieved at a cost that is less than the social costs of CO2 emissions, estimated by the EPA to be somewhere between $12 and $117 per ton in 2015. To minimize the cost of avoided CO2 emissions, ideally a residential solar PV system replaces utility energy that is supplied by burning coal, since coal produces the highest CO2 emissions per kilowatt-hour. Likewise, adding solar panels in a location that already receives 100% carbon-free electricity will result in an infinite cost per ton of avoided CO2, since no CO2 emissions will be avoided. The reality at your wall outlet will lie somewhere between these two limits.
I decided to calculate how much it costs to reduce one ton of CO2 emissions by installing a residential solar PV system in Vermont. I then repeated the calculation in every other U.S. state and Canadian province or territory. This estimate assumes that electricity generated within a state, territory or province is consumed there, and that electricity imports constitute a small percentage of total electricity consumed within that state, province or territory.
The first step is to figure out roughly what percentage of today’s wall-plug power is provided by coal, natural gas, nuclear, wind, solar, hydro, geothermal, biomass, etc. The Energy Information Agency (EIA) tabulates, by year and by state, the total amount of electrical energy (in Megawatt Hours, or MWhr) delivered by each type of generating source. For the most recent year available (2011) in each state, the utility and IPP (Independent Power Producer) electrical energy generated by CO2 emitters (coal, natural gas, petroleum liquids) and non-CO2 emitters (nuclear, wind, solar, hydroelectric, geothermal and biomass) was extracted, with the assumption that biomass was carbon neutral. The ratio of fossil fuel to total electrical energy produced was then calculated for each state in 2011. The results ranged from 0.14% fossil electricity in Vermont, to 98.7% fossil electricity in Delaware.
The same tabulation was performed for Canadian provinces and territories using 2011 data from Statistics Canada. In Canada the results covered the entire range, from essentially 0% fossil electricity in Prince Edward Island up to 100% fossil electricity in Nunavut.
Next, the CO2 emissions per MWhr were calculated using the following emissions estimates: 1.4 tons/MWhr for coal, 1.0 tons/MWhr for fossil liquids, and 0.47 tons/MWhr for natural gas. The total CO2 emissions were estimated by multiplying the energy in MWhr produced from each source, by the CO2 emissions per MWhr for each source. The resulting CO2 emissions in 2011 ranged from <0.001 million tons CO2 in Prince Edward Island, 0.008 million tons in Vermont, up to 279 million tons in Texas.
The average CO2 emissions associated with electricity generation in each state, province or territory in 2011 was then calculated by dividing the total CO2 emissions by the total amount of energy generated. The resulting averages ranged from <0.001 tons CO2 per MWhr in Prince Edward Island, 0.001 tons CO2 per MWhr in Vermont, 0.567 tons CO2 per MWhr in Nevada, to 1.36 tons CO2 per MWhr (almost 100% coal) in West Virginia.
The amount of solar energy generated by a solar PV residential system was next estimated. The annual averaged hours per day of full sun for a South-facing fixed solar array tilted at latitude was extracted from the National Renewable Energy Labs (NREL) Renewable Resource Data Center. The values ranged from a low of 2.5 hrs/day in Yukon Territory up to 6.5 hrs/day in Nevada and Arizona. Assuming a 10 kW(AC) system with a 20 year service life and no aging, the total energy delivered by the rooftop solar PV system was estimated in Nevada to be (6.5 hrs/day)*(365 days/yr)*(20 yrs)*(10 kW(AC)*(0.001 MWhr/kWhr) = 475 MWhr of electricity. All of the generated electricity was assumed to be used somewhere in Nevada. This calculation was repeated for every state, province and territory.
The cost of the residential solar PV system was needed next. A recent article at Solar Panels Review gave 2013 price estimates for a contractor-installed system using several panel choices. The average unsubsidized cost was $5.57/Watt AC, or $55,700 for a 10 kWAC system. This unsubsidized cost is assumed to be the same everywhere.
The cost of CO2 emissions avoided using residential solar PV can now be estimated. The cost per ton CO2 avoided is given by the solar PV system cost divided by the total CO2 tonnage avoided over the 20-year life of the system. For example, using the previous estimates for Nevada, the avoided CO2 emissions cost is given by ($55,700)/(475 MWhr*0.567 tons CO2 per MWhr) = $207/ton CO2. This calculation was repeated for every state, province and territory and, as shown in Figure 1, plotted versus the fraction of generation that is free of CO2 emissions.
First, notice that the vertical axis is a logarithmic scale, ranging from $1/ton CO2 (well above the 5 cents/ton that traders at the now-defunct Chicago Climate Exchange determined was an appropriate price), up to $10,000,000 per ton CO2. Several horizontal lines indicate the California carbon exchange price of about $12/ton CO2 and one EPA estimate of around $60/ton CO2. A vertical line marks one widely discussed goal of 80% CO2-free electricity generation.
Note how the use of residential solar rapidly escalates the cost of avoiding CO2 emissions as the power grid moves towards a ‘low-carb’ diet. Also note that even in ‘high-carb’ states at the left side of the graph, residential solar PV is an expensive way to avoid CO2 emissions associated with electricity generation, never breaking below $100/ton CO2. Substituting DOE’s 2020 SunShot goal of $1.50/Watt installed cost for a residential system shifts the curve down, but retains the highly coveted hockey stick shape J.
So, Bill McKibben’s solar panels in Vermont are indeed avoiding CO2 emissions in Vermont (one of the data points at the far right side of Figure 1), at a cost of around $155,000 per ton CO2. This is equivalent to paying a carbon tax of $2.00 for one teaspoon of gasoline.
Figure 1- Semi-log graph showing the cost of avoiding one ton of CO2 emissions using residential solar PV, province or territory, as a function of the carbon content at the wall outlet. Several U.S. states and Canadian provinces are indicated. The two horizontal lines represent two official estimates of the social cost of carbon dioxide emissions.
References-
Salon magazine article-
http://www.salon.com/2013/09/15/bill_mckibben_being_green_wont_solve_the_problem/
Solar insolation data from NREL-
http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/sum2/state.html
Electricity production in the U.S.-
http://www.eia.gov/electricity/data/state/
Electricity production in Canada-
Solar PV system costs-
http://solar-panels-review.toptenreviews.com/
jrwakefield says:
October 22, 2013 at 7:03 am
Chad Wozniak says: “You are forced to chose between accepting that or having a humongously larger electric bill ”
But your FIT participation is what is causing those high power rates. YOU are the cause that everyone else is forced to pay.
No jr, the politicians are the cause. Chad is simply one of the caged hamsters being forced to perform accordingly for his sustenance. However, if Chad voted for those same politicians, then you have a point.
I live in Colorado, sunny some 300 days a year. There are six hours a day for significant solar input to solar panels, solar noon +/- 3 hours. The average daily output expectation on an annual basis is 4.2 Kw per Kw of panels, in Colorado, from the engineers of the installation company. At $.08/Kw for power from the power company, a Kw panel will generate $.336 worth of electricity/day, or $122.64 annually. In fifty years that 1 Kw panel will cover its installation cost of $6000, should it live so long.
The reality is that solar panels will never replace coal generation. Coal is base load since it takes a long time to ramp it up or down. Solar on the other hand can and will change dramatically on a time scale of minutes to seconds. In reality solar, if it replaces anything, will result in a little less peak power production, which is almost always either hydro or natural gas.
Chip Javert says:
October 21, 2013 at 10:54 pm
I have just retired to Florida, and am installing a $36,000 10KW solar system sized to eliminate my $3,000/year electrical bill from Florida Power & Light. Why would I invest in something having a 12 year payback?
Well, I say $36,000, but I get a $2,000 rebate from the HW manufacturer, $20,000 (yep, $20k) from FPL (actually, their rate payers…), and a $10,800 federal tax credit – net installation cost to me after 90 days of filing forms & having stuff inspected is $3,200.
As might be expected, the demographic that can pay $36,000 and wait 90 days to collect $32,800 in rebates/credits tends to skew “upscale”. Oh yea, and the value of my house goes up almost the full $36,000 which (by law) does not increase my taxable property value. Go figure.
Having already made my point about the politicians, you do, I hope, understand why few will sympathize with you if the panels you installed fail in two years, the value of your house drops $70,000 due to the presence of the useless panels (but not the property taxes), de-installation harms your roof, and you’re stuck having to pay not just for electricity generation, but also for all the subsidies FPL has paid out on schemes like this? And then there’s the federal debt that we’re just leaving to our children and grandchildren to worry about, I suppose.
The solution to the subsidy mess is obvious, by the way. Any business that builds itself on a subsidy model undertakes the risk that the subsidies will end (see Spain). Once this nonsense comes to an end, the regulators should lower FPL’s rates to disallow recapture of previous subsidies and let them go bankrupt. The shareholders and debt holders who supported that business model with their funds took the subsidy risk and deserve to take a beating when it ends, not the ratepayers. The reconstituted FPL will then be able to charge a reasonable rate again, i.e., a rate based on the actual cost of generating electricity. (Gee, what a novel concept, no?)
To those who say this can’t happen, I’d reply that it’s just politics. If a politician promises, if elected, to replace the regulators with people who would do as I’ve described, could he get elected someday? Because that’s all it would take.
The cost comparison is on the right track, however, it should be noted that the solar power scam calculates/quotes solar power based on peak energy generated on a sunny day, 10:30 to 13:30, in the summer, and ignores the problem that electrical power demand peaks at around, 18:00 to 20:00, when the sun does not shine.
Battery storage needs to be included with the solar case, as power is required at night for heating, lighting, air conditioning, refrigeration, computers, cell phone chargers and so on.
The cost of providing battery storage almost doubles the cost of the solar installation over 20 years as the batteries have a lifetime of 7 to 10 years and the solar panels a lifetime of 15 to 20 years. It should be noted that the necessary DC to AD inverter, has a lifetime of around 7 years.
The solar example also needs to address the problem of winter (less sun), snow, rain, and cloud cover. Battery storage is reasonable for daily energy shifts, it does not solve the problem of snow and multiple days of heavy cloud cover.
Another back of the envelop method to get a handle on solar costs is to compare actual commercial installations Solar vs. Nuclear. The cheapest new commercial German solar installation is four times more expensive the world’s most expensive new nuclear installation (Finland). The cheapest German solar installation is 12 times more expensive than the newest Chinese nuclear installation. The German solar costs do not include the costs for battery storage or the cost for electrical grid upgrades to transport the solar energy from the region where the solar power is generated to the regions where power is required. Battery storage and power grid up grades doubles or triples the solar costs.
http://thebreakthrough.org/index.php/programs/energy-and-climate/cost-of-german-solar-is-four-times-finnish-nuclear/
If battery storage is not been included in the solar costs, solar can only reduce CO2 emissions by roughly 10 to 15%. As there is a practical limit to the ability of a country to pay for power (increases in the cost of power of say 12 to 15 times are ridiculous), solar power is not viable to achieve CO2 emission reduction of 50%. Nuclear power plants are the only viable engineering solution to reduce CO2 emissions by more than 15%.
It should be noted to reduce world CO2 emissions by 50% or more requires addressing other CO2 sources and hence, requires draconian policies such as the banning of air travel for tourism, the banning of recreation vehicles/boats, and so on. Reductions below 50%, requires forced population reduction as 50% of the CO2 emissions are due to the products that people purchase and the food that they eat.
Reduction in CO2 emissions of 50% only delays the eventual rise in atmospheric CO2. So if the long term is considered and the fact all developed countries are deeply in debt, the best approach (if facts and logic are used to make the decision as opposed to green scam logic) is to optimize nuclear power now (as sometime in the next 100 years we will need to change to nuclear power) and to address the problem of population growth in the developing countries. (There is roughly a billion years of fission nuclear power available from dissolve uranium in the oceans which can be commercially removed, using fourth generation reactors.)
Tom Andersen says:
October 22, 2013 at 6:56 am
“Incentives” as in subsidies? Taxpayer pays AGAIN?? We are going to go broke (See the U.S.) subsidizing all these “green” feel good energy policies. So a person installs $36,000 in solar equipment and gets over $32000 in “incentives” and can brag about how green they are and how much they have “saved”? Something is seriously messed up.
Leonard Weinstein says:
What you are saying is contingent upon external hookup costs. I was quoted 110K to bring power lines into my area which is 3 miles from the nearest access. A 3.5 kw solar system with batteries, passive trackers and a 20kw backup generator cost me 55K. I do live in NE Arizona so have lots of full sun days and the passive trackers gather more than the 6.5 hrs of noon equivalent sun.
William Astley says:
“The solar example also needs to address the problem of winter (less sun), snow, rain, and cloud cover. Battery storage is reasonable for daily energy shifts, it does not solve the problem of snow and multiple days of heavy cloud cover.”
Depends upon the system you have. I live totally off-grid and while I occasionally have snow and multiple days of could cover. Snow I deal with by immediately cleaning the panels in the morning although most times the snow falls off as the passive trackers move then from the evening configuration to the morning configuration. The charge controllers I have for my system maintain a voltage drop so that I can charge batteries even on cloudy days. I have a whole house 20Kw (16 kw because of altitude) backup system I have used it maybe 16 times in the last 4 years to supplement the solar system I have.
Taking a leaf from those Climate modellers, I am thinking of producing a simulated solar panel installation.
I reckon it will take just two pieces of wire to hook up the electricity supply to the feed-in tariff meter. Whilst the electricity meter will whizz around like crazy, so will the feed-in meter. And, the end of the month I should get a really big cheque!
[BTW, those two pieces of wire could also simulate a wind-turbine ]
One big factor I haven’t seen mentioned is all of the energy that goes into the manufacture of silicon solar cells, panels, support structures, etc. In many cases the total output of solar panels throughout their lifetime is less than the energy that went into manufacturing, transporting, and installing them.
Rod says:
October 21, 2013 at 9:19 pm
I think the only useful solar power is when used for heating hot water. Last I calculated it was about a 10 year pay off period (for 38 degrees south) and from then on increasing returns as electricity costs continue to go up.
———————–
I think you are right.
But there is another way of using solar power for heating hot water that will save you a ton of money in the “long run” that doesn’t require the use of solar panels ….. and is a one-time fixed cost to install and is basically maintenance-free thereafter.
Install a 30 gallon un-insulated “tempering tank” in-line between your water input source and your hot water tank.
One will realize a small savings if said “tempering tank” is installed most anywhere inside their home that is maintained at a comfortable temperature.
But now anyone who lives say south of 38 degrees latitude will realize a significant savings if said “tempering tank” is painted “flat” black and installed in the attic of their house where all that solar energy accumulates and will warm up the water in the tank. And in the summer months will heat up that water to 100+ degrees. (Unless they have a lot of ventilation to keep the attic cool)
How much CO2 is produced just to make the solar panels in the first place?
Rod Everson says:
October 22, 2013 at 7:45 am
“No jr, the politicians are the cause. Chad is simply one of the caged hamsters being forced to perform accordingly for his sustenance. However, if Chad voted for those same politicians, then you have a point.”
GLOBE international controls the energy policy of EVERY established party in the West.
(You can of course vote for outsiders who will be kept out of the parliaments.)
John Bowman says:
October 22, 2013 at 7:17 am
I thought the sole purpose of installing solar panels on the roof was to make money, by taking it out of the bank accounts of all those electricity users who do not have solar panels, and transferring it into the bank accounts of those that do, via feed-in tariffs. At least that is the case in Europe.
A practice for which the term ‘daylight robbery’ is most apt: having solar panels on the roof is just a means to avoid it falling under the definition of theft according to Common Law.
————-
EXACTLY!
“Battery storage needs to be included with the solar case, as power is required at night for heating, lighting, air conditioning, refrigeration, computers, cell phone chargers and so on.”
Actually, the home only runs off the batteries, and during the day the solar’s job is to charge those batteries, unless you’re the kind of person who is willing to have no power when there is no sun.
The real dilemma is how many panels one needs. You cant use a day period of consumption, you need to be able to run your home off the batteries for several days with no recharging (for those long cloudy winter days). That means you have to have enough panels such that in one day they charge for those batteries for 3 or 4 days of usage. Good luck doing that here in Canada.
1. Economies of scale have reduced cost of solar system installed in Germany to $2.24 per watt, that is with a slightly higher labor cost:
http://www.greentechmedia.com/articles/read/German-Solar-Installations-Coming-in-at-2.24-Per-Watt-Installed-U.S-at-4
2. You are not including transmission line losses in your MWh calculation. The EPA emissions are at the generator, the avoided emissions for a residential installed system are at the meter so emissions avoided need to be increased by about 8 percent.
4. The EPA shows an increasing cost over time even with a discount rate so that the 20 year average is much larger than the avoided cost value of 2015. (about 3X the 2015 value by 2035)
for example:
5. If CO2 avoidance was the only benefit of solar power then no one would install solar on their roofs. Many people have installed solar on their roofs and some are even making money doing it. The application of avoided emissions and societal costs for this calculation should be removed from the cost of the system as compared to the grid system. i.e. a carbon cost of a fossil fuel system is 4 cents per kWh and increasing over the life of the system (20 years) to 12 cents per kWh avoided. Therefore, over the over the life of a system the average avoided cost is 8 cents per kWh. for a lifetime generation of 475 MWh, the savings of the system of social cost of carbon is $38,000
The real efficiencies of solar power don’t count here in Vermont. It’s sustainability is totally artificial.
GMP Solar is a net metering program that pays customers who generate solar energy. The amount a customer receives is based on the value of the energy that GMP charges the customer, plus an additional 6 cents per kilowatt-hour generated by solar arrays. – See more at: http://www.greenmountainpower.com/innovative/solar/faqs/#sthash.50dgXCT3.dpuf
So they pay $.06 /kwh more than the going retail price for solar. No retailer can buy product for more than they sell it for without something fishy going on. It certainly will be sustainable as long as the rest of us are taxed enough to fill in the losses.
“(There is roughly a billion years of fission nuclear power available from dissolve uranium in the oceans which can be commercially removed, using fourth generation reactors.)”
Fission will never happen. Liquid Fluoride Thorium Reactors is our future, iff rational minded people were running the asylum.
Sorry, meant fusion, is that that what you meant too?
Rod Everson says:
October 22, 2013 at 7:45 am
No jr, the politicians are the cause. Chad is simply one of the caged hamsters being forced to perform accordingly for his sustenance. However, if Chad voted for those same politicians, then you have a point.
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No, he is regardless. We have FIT here, but I refuse to get involved because I know my power savings will be at the expense of others, such as my own kids. So it’s a MORAL choice to suck on the FIT teat.
RACookPE1978 says:
October 21, 2013 at 9:45 pm
No, there are NO pumped storage sites “allowable” for use right now. NONE.
Not sure what your definition of pumped storage is but here is a link to a pumped storage system in Michigan. http://www.consumersenergy.com/content.aspx?id=1830
I’ve been to the small lake sitting above Lake Michigan just out side Ludington, Michigan.
Meanwhile over at Climate Depot:
‘How Government Is Making Solar Billionaires’ – ‘How Gore & billionaires profiteer on taxpayer subsidies for solar energy
http://www.climatedepot.com/2013/10/22/analysis-how-gore-billionaires-profiteer-on-taxpayer-subsidies-for-solar-energy/
In reply to:
chemman says:
October 22, 2013 at 9:04 am
William Astley says:
“The solar example also needs to address the problem of winter (less sun), snow, rain, and cloud cover. Battery storage is reasonable for daily energy shifts, it does not solve the problem of snow and multiple days of heavy cloud cover.”
Depends upon the system you have. I live totally off-grid and while I occasionally have snow and multiple days of could cover. Snow I deal with by immediately cleaning the panels in the morning although most times the snow falls off as the passive trackers move then from the evening configuration to the morning configuration. The charge controllers I have for my system maintain a voltage drop so that I can charge batteries even on cloudy days. I have a whole house 20Kw (16 kw because of altitude) backup system I have used it maybe 16 times in the last 4 years to supplement the solar system I have.
William:
You comment (an anecdotal comment of one person who lives ‘off grid’) is unfortunately one of the reasons why there is a myth that green scam energy is viable. It is not viable for the following reasons.
It is a fact that the developing countries have spent 2 trillion dollars on green scam energy and it has made no practical difference in world CO2 emissions.
Why is that true? How is possible to spend 2 trillion dollars on green scams with no practical difference in CO2 emissions? What is logically the reason for that paradox?
The term ‘off grid’ ignores the fact that 50% of the CO2 emission in every country is due to the goods we purchase and food we eat. Roughly 25% of our energy requirements are for the automobiles we drive and the air flights we take for holidays. The electricity used for a residential home is roughly 25%.
The problem of scalability (one person can live off grid an entire country including industrial production cannot live off grid), concentrated energy requirements for good production, and forcing uneconomic changes to take place by a deadline are just some of the show stoppers.
Green energy does not work due to economics (the amount of surplus funds countries have to spend) and engineering reasons (power storage is required, the energy input to construct and maintain the green scams needs to be included) to reduce CO2 emissions for an entire country and for all countries by say 50% by 2030 or 2050. It should be noted that the developing countries are developing. The people in those countries each want air conditioning, a refrigerator, television, computers, automobile, and so on.
There are a number of good books that have been published that start to address the reality of the energy issue rather than myths.
The following are two which I would recommend.
http://www.dieterhelm.co.uk/
http://www.dieterhelm.co.uk/
The Carbon crunch: how we are getting climate change wrong and how to fix it, by Dieter Helm
Helm is a true liberal academic. He admits that the money spent on green scams has made almost no practical difference in the CO2 emissions. He alludes to the fact that nuclear power will work, but adds that nuclear power is politically not viable in the EU. Helm’s solution to force a change on a time table is a draconian carbon tax, however, Helm neglects to explain the economic and political impact of increasing the cost of energy by a factor of three or four. The end of air travel for tourism for example, which is roughly 13% of the EU GDP, the transfer of jobs to lower energy regions unless all countries enact the draconian carbon tax, an increase in the cost of goods and food by roughly 50% to 75%. It is a fact that higher energy costs will result in a lower standard of life.
Energy Myths and Realities: Bringing Science to the Energy Policy Debate by Vaclav Smil
This is an article by Vaclav Smil that includes some of the basic facts concerning the energy policy debate which is discusses in more detail in his book. Smil is realist which is some what different than a skeptic. Smil lays out engineering reality for energy use and requirements on a country and world basis.
http://spectrum.ieee.org/energy/renewables/a-skeptic-looks-at-alternative-energy/0
A Skeptic Looks at Alternative Energy, It takes several lifetimes to put a new energy system into place, and wishful thinking can’t speed things along, By Vaclav Smil
I stand by my statement, but obviously need to explain my terms better.
I am referring to “new” pumped storage sites and to the “next generations” of pumped storage or a large-area-grid-supporting pumped storage that MUST be built/is planned to be built/is already designed and is being built if the grid is to remain stable when “renewals” are more common. Yes, there are several pumped-storage sites around the country – one is fairly close to me across the border in mid-Tennessee. How many more sites will be needed, and where are they to go?
BUT it – like all of the pumped storage units around the country – are already at peak use. IF solar or wind is implemented past today’s 2% generating “capacity” we will need thousands of pumped storage sites. Pumped storage requires essentially EVERYTHING a “normal lake” requires: A dam in a valley with suitable rock and geology to take the pressures of the dam safely; or a constantly-flowing, non-freezing river as a water source. An upstream/uphill “flat” spot ALSO suitable for a dam or looooong dike that the enviro’s will support and on land that is affordable and is NOT being used for something else. Needs to be on the existing grid – after all, ALL of its energy needs to be either coming in or going out every hour. Smaller requirements are access, area for the pumps, land rights and enviro permits for the pumps, transmission towers, switchyards, control buildings, transformers, repair sites, etc.
What I said holds true across the country: There are no plans for new pumped storage sites being pursued across the EPA/WWF/Greenpeace/Dept of Interior and all of their obstacles. There are no more available anywhere in the country sites for “new” or expanded pumped storage sites capable of storing any portion of today’s power needs.
RACookPE1978 says:
October 22, 2013 at 11:29 am
OK.