Larry Gray
Hw06
MMEES
Oct 21, 2014
Problem 2)
The Jacobson et al. paper described a plan to convert all of New York State’s (NYS’s) all-purpose energy
infrastructure to one using only wind, water and solar energy by 2030. All aspects of the plan were
thoroughly thought out and described. The plan described the contribution from wind, water and solar
as follows:
40% of NYS’s 2030 energy needs would be supplied by offshore wind located off the coast of
Long Island. Another 10% of the energy needs would be supplied by on-shore wind throughout the
state. Hydro-electric power would contribute another 5.5%, of which 89% is currently being supplied.
The construction of solar PV and concentrated solar plants (CSP) would each supply another 10%,
respectively, of NYS’s energy needs. Installation of residential solar PV systems would supply another
6% and solar PV systems on commercial and government rooftops would supply another 12%. In
summary solar power would contribute 38% of NYS’s 2030 energy needs and wind would supply
another 50%. Hydro-electric would supply 5.5% and geothermal energy would supply 5%. The
remaining 1.5% would come from wave devices and tidal energy.
The paper had presented estimates of NYS current energy demand in 2010 based on the use of
fossil fuels and wood. The energy demand using fossil fuels and wood was then projected for 2030.
Finally the author projected the amount of energy demand for 2030 using only wind, water and solar
energy which showed a reduction of 37% from that of conventional fossil fuels and wood. This
reduction in energy demand was explained as follows: A 5-10 percentage points was assumed for
improvements in energy conservation measures. Since these estimates for energy demand started from
global and U.S. estimates, from which NYS energy needs were derived, the energy demand includes
energy required for upstream processes to mine the coal, oil and gas which would not be required for a
wind, water and solar scenario. Also you wouldn’t have the upstream fuel processing energy for
enriching uranium or refining the crude oil. The last contributing factor is the use of electricity for
driving electric motors is more efficient than the efficiency realized in converting thermal energy from
combustion to mechanical energy in heat engines. The one problem I have with this last contributing
factor while it may be true that electric motors are more energy efficient, I don’t think they can produce
the power density that comes from current heat engines. For example, electric powered aircraft
powered by the sun are more a novelty currently as they can only power small aircraft with one pilot
and no passengers. The power from a single turbofan engine powering the large aircraft has thrust
ratings up to 115,000 lbs. Maybe the future of aviation could be that it will take many small electric
motors to power a commercial airplane.
The main concern I had when reading this plan was what does NYS do when the wind isn’t
blowing and the sun isn’t shining? Wind and solar energy are highly intermittent and at the latitudes of
NYS, the solar insolation for Albany NY average’s about 4.3 kWh/m2/day. The authors had estimated a
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range of 4 to 4.5 kWh/m2/day, so the estimate is reasonable. The authors did take this intermittency
into account when developing the plan. Their solution is to oversize the power required to satisfy the
peak demands and produce excess electricity which would then need to be stored for use when solar
and wind energy is not available. The paper described several storage options from thermal storage in
molten salts, storage of compressed air in underground caverns, hydro pump storage and the use of the
extra electricity produced during the peaks to electrolyze water to produce hydrogen that could later be
used for heating or electricity production. So with the implementation of storage technology this plan
just might work. The other parts of the plan describe demand management, such as using demand
response (financial incentives to shift the usage of electricity to off-peak times) to better align demand
with supply. This demand management part of the plan may be problematic in that is will require
people to adapt life style changes and change is often not received well. This may be the most difficult
part of the plan and the authors did recognize it. Switching from current combustion engine driven
automobiles to battery-electric or hydrogen fueled hybrid electric vehicles may be difficult for many
people who have become accustomed to the power of their current vehicles. Currently you don’t see
very many electric pickup trucks. Maybe in the near future electric powered pickup trucks will deliver
more power and will become more acceptable to that segment of the market. The other aspect that will
require a lifestyle change is the time it takes to re-charge a vehicle. The paper describes that for high
voltage (440v) recharging stations, the time it takes to recharge a vehicle is 1 hour. In the current fast
paste society we live in, this will require some lifestyle changes.
In summary, I think the plan is well thought out and described very well. The paper even describes
costs, paybacks, tax revenues, job creation, externality costs from fossil fuels which will be saved which
were not described here in this short summary. With the development and improvements to storage
technology I think this plan could be implemented. The upfront costs will have to be managed through
incentives and financing so as the average person in NYS would not be overburdened with switching
costs. Job re-training will need to be a part of the plan to help with the change of lifestyle. The lifestyle
changes required will be an aspect of the plan that will be met with large amount of resistance so
dealing with this resistance will have to be thoroughly thought out for the implementation of such plan
to be successful.
The Fraunhofer Institute presentation shows the electricity production in Germany from solar and wind
for the first 7 months of 2014. Slide 4 shows the amount of installed capacity of nearly 35 GW of wind
and 37 GW of solar in Germany. Germany has 77 GW of combined capacity in coal (brown and hard)
and gas. The combined wind and solar capacity add up to 72 GW. However slide 5 shows the actual
energy production for the first 7 months of 2014 and a large share of the energy produced was from
coal and gas at a combined 157 TWh. Solar and wind energy production add up to a combined 52 TWh
which represents about one-third of the energy provided from coal and oil and yet the installed
capacities are nearly the same. This just illustrates the intermittency of the wind and solar energy. The
other takeaway is the energy produced from nuclear energy was 51 TWh which is nearly the same as
that from solar and wind. In the wake of the Fukushima nuclear power plant disaster in Japan, Germany
wants to shut down their nuclear power plants. Currently Germany is adding energy produced from coal
to offset the reduction in nuclear energy and this is creating a conundrum for their greenhouse gas
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reduction strategy. Slide 7 presents the change in energy production composition for the first 7 months
of the year where gas has been reduced by 24%. While gas is cleaner energy than coal, the politics of
the day are factoring into the decision to reduce energy production from gas so as not to be reliant on
gas from Russia. Brown coal energy production is down only 5% whereas that from hard coal is down
over 11%. Brown coal is a “dirtier” coal but that is the coal that is available in Germany. Nuclear is
down only 2%, but the long-term plan is to shut down all the nuclear power plants by 2022. Now, the
nuclear energy is going to have to be replaced with either more solar and wind or with burning more
coal, if Germany doesn’t want to rely on gas from Russia. Slides 10 and 11 show the monthly energy
production from solar and wind and these 2 slides also show the intermittency of these renewable
energies. One good outcome was that the solar and wind when combined tended to provide a constant
energy source. Slide 12 shows the month to month energy production from conventional (fossil,
nuclear) fuels and the consistent reliable energy production from month to month. Slide 14 shows that
the overwhelming majority of the energy in Germany still comes from fossil and nuclear power. The
remaining slides in the presentation show more details from monthly to daily energy production, but the
conclusion is that Germany’s energy policy still relies heavily on fossil fuel and nuclear energy, even with
all that solar PV and wind capacity. In the wake of the Fukushima nuclear powerplant disaster in Japan,
public sentiment is calling for shutting down the nuclear power plants and that is creating a problem for
the German energy policy in how to replace the power produced by nuclear without conflicting with
their environmental policy to reduce CO2 emissions and also not to be reliant on Russian gas.
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