I have three major themes in this letter:
A) We likely have greatly underestimated the difficulty in reducing greenhouse gases by 80%, relative to
releases in 2005, by 2050,
B) How we might overcome the above situation, and
C) Insights on how to form a mix of energy sources.
A.UNDERESTIMATING THE TASK AHEAD
A.1 Achieving electric power sufficiency
The USA’s electric power industry faces enormous challenges. Based on studies by the International
Panel on Climate Change, by 2050 the worldwide release of greenhouse gases (GHG) must be reduced by
about 80%, relative to releases in year 2005, in order to prevent the worst effects of climate change.
Today about 39% of the GHG releases in the USA can be attributed to the burning of fossil fuels, mostly
natural gas and coal, in our electric power plants. Yet these same fossil fueled plants produced about 67%
of the nation’s electricity in 2012. In 2012 about 19% of the USA electricity production came from
nuclear power plants. By 2050, it is very likely that all of the presently operating nuclear power plants
will be retired because their licenses would have expired. Between the phasing out of fossil fueled electric
power plants and the retirement of operating nuclear power plants, by 2050 some 86% of the year 2012
electricity production would no longer be available. Of the remaining 14% of the electricity production in
2012, about half was provided by large hydropower facilities and further expansion of this electricity
source is problematic. The remaining 7% attributable to renewable energy comes mainly from wind
power and solar energy systems like photovoltaics. These renewable energy sources are variable and
intermittent. As stand-alone systems these renewable energy sources will likely need very large
investments in energy storage to be able to rapidly match the varying demand for electricity with high
reliability, as is now accomplished with our present mostly fossil fueled/nuclear electric supply system.
Providing sufficient carbon-free electricity by 2050 is an enormous challenge. Where will all this carbonfree electricity come from? Putting aside possible increases in demand from population growth, greater
electrification of our transportation system, more use of robotics, and the effects of climate change, just
matching the electricity production of 2012 with carbon-free electricity would require trillions of dollars,
at present capital costs per kilowatt of capacity ( I can provide the calculations to support this) and would
require the equivalent of putting over two 1,000 Megawatt-electric power plants, operating at a 90%
capacity factor, on line every month for the next 417 months. This appears to be well beyond our present
manufacturing capacity, particularly if this growth in carbon-free electricity sources has to take place in
competition for capital, materials, and labor needed for the essential growth in electrified transportation,
e.g., tens of millions of electric cars, and the creation of carbon-free liquid fuels or no-net carbon liquid
fuels, as discussed below.
A.2 The Energy System-Wide Carbon-Free Continuum
The residential + commercial sectors together account for about 10% of the GHG releases in the USA
today. While not as large as the GHG release in the transportation sector or from electricity production,
achieving carbon-free residential + commercial sectors appears to be necessary in order to meet the IPCC
goals.
However, the necessary changes that must be implemented by 2050 in the residential and commercial
sectors goes beyond eliminating the approximately 10% of the GHG releases. We appear to have a
planning disconnect that few seem to be talking about. Even if all sources of electricity were totally
carbon-free by 2050, this would not be enough. To illustrate this, consider a utility that brings carbon-free
electricity into someone’s home only to discover that the space heating system in this home burned a
fossil fuel, like natural gas. The carbon-free electricity would be of little use for space heating in this
example because it would not be compatible with the existing space heating end use device. In today’s
energy system the sources of energy, the transmission and distribution networks, and the end use devices
are all in harmony so that all the energy consuming sectors: transportation, industry, commercial, and
residential, can fully function. This system-wide harmony, however, is largely based on fossil fuels. To
meet the goals of the IPCC a new carbon-free system must be created that also brings energy sources,
transmission and distribution networks, and end use devices back into harmony. Without achieving a new
system-wide harmony, the efforts to produce carbon-free sources of electricity will be wasted and
insufficient to achieve the goals of the IPCC. We need an energy system that enables a carbon-free
continuum.
Achieving a system-wide carbon-free continuum is not a simple task. For example, there are 132 million
housing units in the USA and tens of thousands of businesses. If each housing unit or business had, on
average, about 2.6 fossil fueled end use devices, we are looking at replacing about 350 million such end
use devices over the next 35 years, until 2050. On average, this comes to replacing 10 million end use
devices each year for the next 35 years. Can we even produce and install 10 million carbon-free end use
devices each year? Perhaps we should start with eliminating the release of GHGs from space heating and
hot water end use devices with new end use appliances that would be energized from non-carbon sources
of electricity, such as renewable energy and nuclear energy.
A.3 Liquid fuels
The “California’s Energy Future” report is an excellent analysis of what California would have to
accomplish to achieve a carbon-free energy future. After emphasizing conservation, after expanding
electrified transportation and after using a mix of nuclear power and renewable energy, this report
concluded that it still could not meet its goal of a carbon-free future. The stumbling block was the need to
use high energy density liquid fossil fuels in various transportation modes, like air travel. We will need to
develop carbon-free or no- net carbon high energy density liquid fuels in sufficient quantities by 2050.
A.4 Areas Outside of the USA
An estimated 20%-30% of the GHG released to the environment comes from rural, off-grid locations such
as in India, Africa, and Southeast Asia where billions of people live. Unless these sources of GHG are
curtailed, the goal of the IPCC will not be achieved.
B. HOW THE ABOVE CHALLENGES MIGHT BE OVERCOME
B.1 Sufficient Electricity
Because of very large capital costs and because of limits to our manufacturing capabilities, a future noncarbon electricity system would have to be significantly smaller than the system we have today, yet
adequate to meet future demands. A future national electricity system should be highly reliable, cost
effective so that the international competiveness of the USA would not be compromised, and flexible
enough to readily evolve into even more superior systems as new technology becomes commercially
viable.
Five steps are suggested for our electricity future:
a. Reduce the demand for electricity through more efficient end use devices and better insulated buildings,
b. Extract appreciably more electricity from a given fleet of power plants than we do today,
c. Multiply the usefulness of the generated electricity through heat pumps,
d. Lower the capital costs of new carbon-free sources of electricity through standardization, modular
construction, and with much lower financing costs,
e. Have a diverse supply of electricity.
Items b and e, above, are discussed further here:
b. Extract appreciably more electricity from a fleet of power plants than we do today
The key to extracting appreciably more electricity out of a given number of power plants and from
renewable energy sources is to utilize low cost energy storage. Low cost energy storage would permit a
shift in electricity production to off-peak time periods. This stored energy would then be used during later
high demand periods. This would be particularly valuable in dealing with air conditioning loads which
often drive peak demand in warmer weather. Peak demand, even though its duration is relatively short
compared to the length of a full year, has significant impact on the average price of electricity and can be
the driving force behind the need for new capacity and for expanding the electrical transmission and
distribution grids, both of which are very expensive and frequently precipitate public resistance and
litigation.
The importance of having low cost energy storage can be appreciated by examining the following
analysis: In 2010 the USA had an electricity production capacity of 1039.1 million kilowatts. If it were
possible to run these power plants 100 % of the time, they would have produced 9,102,516 million
kilowatt-hours. However, the actual production of electricity in 2010 in the USA came to 4,100,656
million kilowatt-hours, about 5,000,000 million kilowatt-hours less than the theoretical limit, i.e., the
actual production was about 45% of the theoretical limit. Stated differently, we need to move away from
our present sine wave electricity production profile to a much flatter electricity production profile. As this
flatter distribution is achieved more electricity would be extracted per plant, on average, thereby reducing
the number of new power plants that need be constructed to meet the demands for carbon-free electricity.
The key to this flatter profile is low cost energy storage. If this low cost energy storage is distributed, i.e.,
placed at or near the point of end use, such as in homes and businesses, then the need for expanding the
transmission and distribution grids would also be significantly reduced.
Shifting air conditioning electrical loads to off-peak time periods serves as a good example of the great
importance of distributed low cost energy storage. Suppose that out of the about 5,000,000 million
kilowatt-hours of annual unused electricity production, 20%, or 1,000,000 million kilowatt-hours of
electricity, normally used to run air conditioners, was shifted to off-peak time periods through the use of
low cost energy storage. Producing and delivering these 1,000,000 million kilowatt-hours of electricity
during off-peak time periods would not require any increase in the number of power plants or expanding
the transmission or distribution grids. It would also somewhat reduce the releases of GHG gases as the
nation moves towards its goal of a non-carbon electricity future. This limited reduction in GHG releases
would occur because the power plants available during off-peak time periods generally are more efficient
(fewer grams of carbon dioxide released per kilowatt-hour) than those plants put into service during peak
demand time periods.
One GHG-free 1000 MWe power plant operating at a 90% capacity factor would produce 7,884,000
MWe-hours each year. Shifting 1,000,000 million kilowatt-hours of electricity to off-peak time periods
would be the equivalent of the output from 127 1000 MWe power plants operating at a 90% capacity
factor. To put this in perspective, this shift to off-peak time periods moves more electricity production
than the output of all the nuclear power plants in the United States. This shift to off-peak time periods of
1,000,000 million kilowatt-hours means that 127 new carbon-free 1000 MWe power plants need not be
built. If one assumes that a new carbon-free power plant could be constructed at a capital cost of
$3000/kilowatt-electric, then 127 fewer 1000 MWe plants would create a savings of $381 billion dollars.
This huge savings could/should encourage centralized utilities to invest in or subsidize low cost energy
storage systems.
Professor Tester and I are developing a proprietary low cost energy storage system that would be capable
of accommodating this air conditioning shift, plus providing carbon-free space and hot water heating, all
driven by off-peak electricity from the grid and/or from distributed renewable energy sources. As the
sources of electricity approach a totally carbon-free condition, the space heating and hot water functions
operated by this low cost energy storage system would also become carbon free. Thus the combined
benefits of low cost energy storage include the money savings is largely due to the air conditioning shift,
with some abatement in GHG releases, plus the additional benefit of further GHG abatement by replacing
fossil fueled space and hot water heating with carbon-free electricity. Low cost energy storage is the
enabling technology that creates the harmony between carbon-free sources of electricity and carbon–free
end use devices. A presentation on this technology to future MIT Low Carbon workshops might be
possible after ongoing steps to protect this intellectual property have been completed.
e. Have a diverse supply of electricity.
Nature uses diversity as one of several basic means of survival against common causes of failure, like
pandemics, droughts, etc. A diverse mix of renewable energy and nuclear power is recommended here. It
is believed that a mix of nuclear energy and renewable energy would have a higher probability of
protecting humans and the environment against extreme events than an all-nuclear or all-renewable
energy future. We have already seen the benefits of diversity in the electric system where extreme cold
disabled coal plants which could not move the coal stored on site to the power plant because the coal was
frozen and coal moving equipment ran into difficulties. Similarly, when lake and river water levels
dropped too low to provide cooling water to thermal power plants along these bodies of water, electricity
from non-thermal sources, such as wind turbines and solar panels, became more valuable. Natural events,
like the huge volcanic explosion at Mount Tambora in 1815. blasted 12 cubic miles of gases, dust, and
rock into the atmosphere. Climate experts believe that the Tambora explosion was partly responsible for
the unseasonable chill that affected much of the Northern Hemisphere in 1816, known as the “year
without a summer”. According to the Smithsonian Magazine , “ The material that it ejected into the
atmosphere perturbed climate, destroyed crops, spurred disease, made some people go hungry and others
to migrate.”
A repeat of the Tambora eruption would be particularly damaging in a highly renewable energy future
which depended on biomass for the production of liquid fuels like ethanol and on photovoltaic systems
for the production of electricity. To a certain extent the nuclear accidents at Fukushima, which led to the
closure of all of Japan’s nuclear plants, at least temporarily, also supports the importance of diversity.
However, there may be an even more compelling reason to develop a diverse energy system because of
another extreme natural event: climate change. We are in a very difficult race against time to install
enough new carbon-free electric power sources by 2050. Nuclear power plants and renewable energy
systems have different manufacturing processes and supply chains and can proceed in parallel without
either slowing down the production of the other. Diversity of non-carbon electricity sources means that
the rate at which GHGs could be abated would be maximized and improves our chances for meeting
IPCC goals more likely. This need for diversity underscores the folly of ideologies that insist on a single
source of non-carbon electricity.
B.2 Liquid Fuels
Like many resource extractive industries, oil and natural gas are extracted from the earth’s crust, used
(burned in this case), while creating waste products which often present large environmental issues. In
general, such extractive industries use once-through processes. For example, oil is extracted from the
earth’s crust, burned, and GHG are released to the atmosphere, some of which then enters the oceans from
the atmosphere, acidifying the oceans. This once-through process needs to come to an end, yet high
energy density liquid fuels are essential for some forms of transportation.
Research is underway to replace this once-through process with a recycle process that would produce
high energy density liquid fuels with no net carbon production. The starting point of this recycle would be
the present carbon sinks, the atmosphere and the oceans. Carbon dioxide is removed from the air or from
the top layer of the ocean where its concentration is at its highest, broken into carbon and oxygen and
combined with hydrogen to produce methanol or other hydrocarbons that can be used as liquid fuels. The
hydrogen comes from splitting water atoms. The energy needed to recombine carbon dioxide and water
into a hydrocarbon liquid fuel would come from nuclear energy and/or renewable energy. After this
hydrocarbon liquid fuel is burned, carbon dioxide is formed which then re-enters the atmosphere and the
oceans with the result that there is no net carbon added to these carbon sinks. The amount of carbon
dioxide originally removed from the carbon sinks equals the amount of carbon dioxide generated by
burning the liquid fuels this recycle process produced. Extracting carbon dioxide from sea water may
eventually be more attractive than extracting carbon dioxide from the atmosphere because of the
availability of water (sea water in this case) and thereby may prevent water usage issues on land.
Professor Forsberg knows far more about these processes than I do and is familiar with efforts made by
the US Navy to use sea water to make hydrocarbons.
C. INSIGHTS ON FORMING AN ENERGY MIX
C.1 The Non-Carbon Electricity Mix
A rough rule of thumb is that population density will significantly influence the mix of non-carbon
electricity sources. It makes no sense to place a large 1000 MWe nuclear plant in a rural off-grid area.
However, worldwide, billions of people live in such areas and, as mentioned before, a large portion of the
world’s GHG releases come from these areas. Similarly, the electricity needs of high population density
urban areas may not be fully met by many present renewable energy sources, such as wind turbines and
photovoltaic panels. In urban areas, not only is the demand/square mile quite high, there are zoning
restrictions, building-to- building shadowing, limited roof-top areas. While some renewable energy
sources can be placed in urban areas, the bulk of the non-carbon electricity in urban areas would likely be
grid based, as it is today. So there is an inherent influence of population density on the selection of which
non-carbon energy sources makes the most sense.
Security issues come into play here also, in this world where cyber attacks are a frequent occurrence.
Because of the vulnerability of the transmission networks to terrorist attacks, there are benefits to
minimizing the distance between the source of electricity and the end use devices. This situation favors
distributed renewable energy sources, distributed low cost energy storage placed near the point of end use,
and small modular nuclear power plants which could be economically installed over a wide range of
population densities. Such highly secure small power plants could supply electricity any where there is a
grid and could, in emergency conditions, become dedicated sources of electricity that supply essential
electricity to critical functions (e.g. water supply, fire and police departments, communications facilities,
airports, military and National Guard bases).
Thus there is room for and there is a need for a mix of renewable and nuclear electricity.
C.2 A New Renewable Energy Paradigm?
Electricity from renewable energy can be divided into two broad categories, local distributed renewable
electricity (Photovoltaic collectors on your rooftop or near by, small wind turbines) and large centralized
facilities like wind farms, solar thermal (power towers). Looking at what is happening in Germany, we
may be seeing the beginning of a significant push back on renewable energy by people who have long
supported “Energiewende”. Such a push back was recently reported in an article in the NY Times. This
resistance is because people are opposed to having electric power lines cross their property and in
Germany much of the renewable energy is made in the north while much of the demand is in the south of
the country. Resistance to new transmission lines, including electricity, oil, and natural gas transmission
networks, is commonplace in the United States. This resistance is particularly acute when the people who
have to put up with these expanded energy distribution networks are not the same people who benefit
from these expansions.
If one refers to the Executive Summary in the National Renewable Energy Laboratory’s “Renewable
Electricity Futures Study”, Figure ES-8, it shows that to reach a situation where renewable energy would
supply 90% of the nation’s electricity, the additional (new) transmission capacity would have to increase
by about 200 million megawatt-miles. This can be compared to the existing 150 million MW-miles
assumed by the NRL computer model and 200 million MW-miles estimated by the Department of
Homeland Security. In other words, about a doubling of the transmission network would be required to
have high penetration of renewable electricity. This appears unlikely to be publically acceptable and the
growing resistance to further expansion of Energiewende appears to be happening at considerably less
than a doubling of their transmission network.
The above transmission issue implies that local distributed renewable energy may enjoy more US public
support than large centralized renewable electricity sources, some time in the future. With regard to new
large centralized nuclear power plants, significant numbers of them could be located on the same sites as
the present nuclear plants and on phased out coal as gas plant sites, achieving further savings by using
much of the existing sites’ and transmission and distribution infrastructure.
Returning to the issue of liquid fuels, perhaps the best use of large offshore wind power facilities would
be in the production of methanol, instead of electricity. This would have the additional benefits of
eliminating concerns that renewable electricity could cause grid instabilities, that fossil fueled power
plants need be in a standby mode to compensate ( and releasing GHG because of this) for the variability
in renewable electricity production, and making of liquid fuels can be done intermittently. .as the wind
blows … because there is no need to match supply and demand on a moment-to-moment basis. The liquid
fuel itself becomes the energy storage medium. No-net carbon liquid fuels might command higher prices
than producing electricity, making this application of renewable energy more competitive. There would
be no need to connect offshore wind turbines to onshore facilities with an expensive underwater cable
system.
A new paradigm for renewable energy might be a mix of off-grid centralized renewable facilities making
no- net carbon liquid fuels and local distributed renewable electricity sources feeding their DC electricity
into the low cost energy system that Professor Tester and I are developing.
Herschel Specter, President
Micro-Utilities, Inc.