Intermittent renewables–wind and solar photovoltaic panels–have been
hailed as an answer to all our energy problems. Certainly, politicians
need something to provide hope, especially in countries that are
obviously losing their supply of oil, such as the United Kingdom.
Unfortunately, the more I look into the situation, the less intermittent
renewables have to offer.
1. It is doubtful that intermittent renewables actually reduce carbon dioxide emissions.
It is devilishly difficult to figure out whether or not any
particular energy source has a favorable impact on carbon dioxide
emissions. The obvious first way of looking at emissions is to look at
the fuel burned on a day-to-day basis. Intermittent renewables don’t
seem to burn fossil fuel on day-to-day basis, while those using fossil
fuels do, so wind and solar PV seem to be the winners.
The catch is that there are many direct and indirect ways that fossil
fuels come into play in making the devices that create the renewable
energy and in their operation on the grid. The researcher must choose
“boundaries” for any analysis. In a sense, we need our whole fossil fuel
powered system of schools, roads, airports, hospitals, and electricity
transmission lines to make any of type of energy product work, whether
oil, natural gas, wind, or solar electric–but it is difficult to make
boundaries wide enough to cover everything.
The exercise becomes one of trying to guess how much carbon emissions
are saved by looking at tops of icebergs, given that the whole rest of
the system is needed to support the new additions. The thing that makes
the problem more difficult is the fact that intermittent renewables have
more energy-related costs that are not easy to measure than fossil fuel
powered energy does. For example, there may be land rental costs,
salaries of consultants, and (higher) financing costs because of the
front-ended nature of the investment. There are also costs for
mitigating intermittency and extra long-distance grid connections.
Many intermittent renewables costs seem to be left out of CO2
analyses under the theory that, say, land rental doesn’t really use
energy. But the payment for land rental means that the owner can now go
and buy more “stuff,” so it acts to raise fossil fuel energy
consumption.
Normally the cost of making an energy-related product gives an
indication as to how much fossil fuel energy is involved in the process.
A high-priced energy product gives an expectation of high fossil fuel
use, since true renewable energy use is free.
If the true source of renewable energy were only wind or solar, there
would be no cost at all! The fact that wind and solar PV tends to be
more expensive than other electricity generation gives an initial
expectation that the fossil fuel energy requirements for creating this
energy source are high, rather than low, if a wide boundary analysis
were to be done.
There are some studies based on narrow boundary studies of various
types (Energy Return on Energy Invested, Life Cycle Analysis, and Energy
Payback Periods) that suggest that there are some savings (from the top
of the icebergs) if intermittent renewables are used. But more broadly
based studies show that the overall amount of fossil fuel energy used by
intermittent renewables is really so high that we don’t come out ahead
by its use. One such study is Weissbach et al.’s study in Energy called Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants. Another is an analysis of Spanish installed solar power by Pedro Prieto and Charles Hall called Spain’s Photovoltaic Revolution: The Energy Return on Energy Invested.
I tend to use an even wider boundary approach: what happens to world
CO2 emissions when we ramp up intermittent renewables? As far as I can
tell, it tends to raise CO2 emissions. One way this happens is by
ramping up China’s economy, through the additional business it generates
in the making of wind turbines, solar panels, and the mining of rare
earth minerals used in these devices. The benefit China gets from its
renewable sales is leveraged several times, as it allows the country to
build new homes, roads, and schools, and businesses to service the new
manufacturing. In China, the vast majority of manufacturing is with
coal.
Figure 1. Energy consumption by source for China based on BP 2013 Statistical Review of World Energy.
Another way intermittent renewables raise world CO2 emissions
indirectly is by making the country using intermittent renewables less
competitive in the world market-place, because the higher electricity
cost raises the price of manufactured goods. This tends to send
manufacturing to countries that use lower-priced energy sources for
electricity, such as China.
A third way that intermittent renewables can raise world CO2
emissions relates to affordability. Consumers cannot afford high-priced
electricity without their standards of living dropping. Governments may
be pressured to change their overall electricity mix to include more
very low-cost energy sources, such as lignite (a very low grade of
coal), in their electricity mix to keep the overall price in an
affordable range. This seems to be at least part of the problem behind Germany’s difficulties with renewables.
If there is any savings at all in CO2 emissions, it would seem to be
from inexpensive intermittent renewables–ones that don’t really need
subsidies. If renewables need a subsidy or feed in tariff, a red danger
light should be flashing. Somewhere the process is using a lot of
fossil fuels in its production.
2. Wind and Solar PV do not fix our oil problem.
Wind and solar PV both are used to make electricity. Our big problem is with oil.
Oil and electricity are used for different things. For example,
electricity won’t run today’s cars, and it won’t run tractors, or
construction equipment, or aircraft. So even if we have more
electricity, it doesn’t fix our oil problem.
Wind and solar PV have been billed as solutions to our CO2 problem.
Unfortunately, as we just saw in (1) above, it doesn’t really do this
either. The combination of (1) and (2) leaves wind and solar PV with
relatively few purposes.
I should mention that there is one small niche where intermittent
renewables can substitute for oil. While oil is not generally burned to
produce electricity, it is used for this purpose on some islands because
of its convenience. These island communities do little manufacturing
because their high cost of electricity makes them not competitive in the
world market. On these islands, intermittent renewables can be used to
reduce the amount of oil used for electricity production, without
driving up the cost of electricity, since electric costs are already
very high.
3. The high cost of wind and solar PV doubles our energy problems, rather than solving them.
The big issue with oil is its high cost of production.
We
extracted the easy-to-extract oil first, and now we are getting to the
more-difficult to extract oil. Adding high priced electricity to our
fuel mix means we have price problems with both oil and electricity,
instead of only one of the two. Consumers’ wages don’t rise to pay for
these high-priced fuels, so disposable income is adversely impacted by
both. The two high-priced fuels also combine to make exported goods even
less competitive in the world marketplace.
4. Even if wind is “renewable,” it isn’t necessarily long lived.
Manufacturers of wind turbines claim lives of 20 to 25 years. This
compares to life spans of 40 years or more for coal, gas, and nuclear. One recent study suggests that because of degraded performance, it may not be economic to operate wind turbines for more than 12 to 15 years.
If we are expecting substantial changes in the years ahead, there are
also issues with whether necessary repairs will really be available.
Wind turbines are especially repair prone. These repairs can’t be made
by just anyone, using local materials. They need the specialized world
supply chain that we have today. Offshore wind turbines sometimes need
helicopters for repairs. If oil is a problem, such repairs may not be
available.
5. Wind and solar PV don’t ramp up quickly.
After many years of trying to ramp up wind and solar PV, in 2012,
wind amounted to a bit under 1% of world energy supply. Solar amounted
to even less than that–about 0.2% of world energy supply. It would take
huge effort to ramp up production to even 5% of the world’s energy
supply.
6. Wind and solar PV create serious pollution problems.
Both wind turbines and solar PV use rare earth minerals, mostly from
China, in their manufacture. Mining and processing these rare earths
generates a tremendous amount of “hazardous and radioactive byproducts.”
In the part of China where rare earth minerals are mined, soil and
water are saturated with toxic substances, making farming impossible.
If we were to try to increase wind and solar by a factor of 10 (so
that they together amount to 12% of world energy supply, instead of
1.2%) we would need huge amounts of rare earth minerals and other
polluting minerals, such as gallium arsenide, copper-indium-gallium-diselenide, and cadmium-telluride, used in making thin-film photovoltaics.
We could not expect China to take on all of this pollution itself.
Instead, the rest of the world would need to produce these toxic
materials as well. Presumably, many countries would require stringent
pollution controls to do this extraction. These pollution controls would
likely require greater use of fossil fuel energy. While pollution
problems might be kept in check, the greater use of fossil fuels would
likely raise both CO2 emissions and the prices of the wind and solar PV.
There are many other pollution issues. China is a major center for renewables production, using coal as it primary fuel. Silicon-based solar cells require heating silica rock to high temperatures in 3000 F ovens,
something that which can be done cheaply with coal. Wind is known for
its noise pollution issues and for killing birds. Solar panels on the
desert floor interfere with the local ecosystem.
A major reason why wind and solar PV are considered clean is because
it is hard to measure their true pollution costs, whether CO2 or other
types. Electric cars have some of the same issues, because they also use
rare earth minerals and have heavy up-front costs.
7. There is a danger that wind and solar PV will make the
electric grid less long-lived, rather than more long-lived. This tends
to happen because current laws overcompensate owners of intermittent
renewables relative to the value they provide to the grid.
One point of confusion is what wind and solar PV really replace. Do
they replace electricity, or do they replace the fuel that makes
electricity? There is a huge difference, in terms of when an
intermittent renewable achieves “grid-parity” in costs. Fuel costs are
typically only a small share of retail electricity costs, so reaching
grid parity is extremely difficult if intermittent renewables only
replace fuel costs. In the US fuel costs average about 3 cents per kWh. For residential users, the retail price averages about 12 cents per kWh, or four times as much as the fuel cost.
What we are interested in is the value of intermittent electricity to
the companies that make and sell electricity–utilities or similar
companies. In my view, the typical value of intermittent electricity is
the value of the fuel the intermittent electricity replaces–in other
words, the cost of coal, natural gas, or uranium replaced. This is the
case because using intermittent electricity doesn’t generally reduce any
costs for an electric utility, other than its fuel costs. It still
needs to provide backup power around the clock to customers with solar
panels. Because of the variability in production, it still needs pretty
much the same capacity as in the past, and it needs the same staffing
for each of the units, even though some of them might be operating for a
smaller percentage of time.
The value of the intermittent electricity to the utility may be
greater or less than the first estimate of the fuel savings. In some
instances, particularly if there is a lot of solar PV in a part of the
world where maximum energy use is during the summer, peak capacity needs
may be reduced a bit. This would be a savings above fuel costs.
Offsetting such savings would be increased costs for new transmission
lines to try to even out spikes in electricity production and to bring
wind from sources where it is strongest to locations where its energy is
truly needed.
The problem that occurs is the fact that most plans reimburse users
of wind and solar PV at a far higher rate than the cost of the fuel they
replace. Often “net metering’ is used, so the user is in effect given
credit for the full retail price of electricity for the electricity
generated by solar panels. This higher reimbursements leaves a revenue
shortfall for the companies involved in producing electricity for the
grid. The danger is that some companies will go bankrupt, or will leave
the system, endangering the ability of the electric grid to provide a
stable electric supply for consumers. This is a potentially much more
dangerous problem than any benefit that intermittent renewables provide.
Also, funding for the additional electric transmission lines is
likely to become a problem, because neither the electricity companies
nor governments have sufficient revenue to fund them. The reason the
electric companies cannot afford them should be clear–they are being
asked to subsidize the costs through overly high reimbursement of the
value of the intermittent renewables. I discuss the reason for the
government lack of funds in (8), below.
8. Adding more wind and solar PV tends to make government finances less sound, rather than more sound.
Around the world, extraction of inexpensive oil and gas has
historically strengthened the finances of governments. This happens
because governments have been able to tax the oil and gas companies
heavily, and use the tax revenue to fund government programs.
Unfortunately, the addition of wind and solar tends to act in
precisely the opposite direction. In some cases, the reduction in
governments revenue comes directly through subsidies for wind and solar.
In other instances, the reduction in government revenue is more
indirect. If the high price of intermittent electricity causes a country
to become less competitive in the world market, this indirectly reduces
government tax revenue because it leads to fewer people having jobs,
and thus less taxable income. Even if the issue is “only” a reduction in
discretionary income of consumers, this still cuts back on the ability
of governments to raise taxes.
9. My analysis indicates that the
bottleneck we are reaching is not simply oil. Instead, a major problem
is inadequate investment capital and too much debt. Ramping up wind and
solar PV tends to make those problems worse, not better.
As I described in my post Why EIA, IEA, and Randers’ 2052 Energy Forecasts are Wrong,
we are reaching an investment capital and debt bottleneck, because of
the higher extraction costs of oil. Adding intermittent renewables, in
which huge costs are paid out in advance, adds to this problem. Because
of this, ramping up intermittent renewables tends to make collapse come
sooner, rather than later, to the countries trying to ramp up these
energy sources.
10. Wind and Solar PV come nowhere near fulfilling the promises made for them.
Trying to substitute expensive energy for cheap is like trying to
make water run uphill. It is virtually impossible to make such a system
work. It makes everyone from governments to businesses to citizens
poorer in the process. Promises that are made regarding future payments
for electricity often need to be reneged on.
If there really were benefits from the program–other than making
government officials look like they are doing something–it might make
sense to expand the programs. As it is, it is hard to see much benefit
to expanding intermittent renewables. Even if we wanted to, there would
be no way we could expand intermittent renewables to cover our entire
electricity program–they are just too expensive, too polluting, and
don’t provide the liquid fuels we need.
Summary
While many people would like us to believe that wind and solar PV
will solve all of our problems, the more a person looks at the question,
the clearer it becomes that wind and solar PV added to the electric
grid are part of the problem, not part of the solution.
If capital is one of the limits we are up against, we need to spend
that capital as wisely as possible. Because solar PV is relatively
long-lived, it is possible it may be a tiny part of the path ahead, but
not as part of the electric grid. Individual citizens may want to buy a
panel or two, as a way of providing some electricity, if we should have
problems with electricity at a later date. But there is no reason the
government should subsidize these purchases.
We might better off spending our capital in more productive ways–for
example, figuring out what path we will follow in the very near future,
if we find we are reaching a financial bottle neck brought on the high
cost of oil extraction. Do we need to be doing more in the direction of
local agriculture, with seeds chosen for each area? Should we even be
thinking about buying up farmland and resettling potential workers to
different areas? Are there ways we can make soil more productive for the
long term?
The primary reason for intermittent renewables was supposedly to
reduce CO2 emissions to prevent climate change. If we seem to be
reaching Limits to Growth in the near term, the amount of
carbon burned will be far lower than the climate models assume–even the
“peak oil” model for future CO2. So perhaps from that point of view, our
inability to make intermittent renewables work doesn’t really matter.
We are already reaching the goal the intermittent renewables were trying
to reach, in another, not very fortunate, way.
We are now faced with the task of trying to figure out what we can
do, in the world Nature gives us. The previous plan didn’t work. Perhaps
we need to find a Plan B that will put us in a better position.
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