December 10, 2008

Commenting on Mark Jacobsons Energy Source Rankings

Mark Jacobson, a professor of civil and environmental engineering at Stanford, has written a review of solutions to global warming, air pollution, and energy security which examines all energy sources. The Jacobson analysis is very biased in favor of wind and against nuclear and biofuels. Nuclear power is burdened with CO2 from "burning cities in the event of a nuclear exchange". Nuclear weapons exist now and building more nuclear power will not increase those risks. Nuclear weapons material were made from special reactors not for generating power or from special enrichment facilities. There can be burning cities from conventional weapons -see world war II bombing of Tokyo, Dresden etc...

I would also propose that if this analysis is valid that we add deaths and CO2 (both from explosions and from the resulting fires) from bomber aircraft to an analysis of passenger jets and add deaths from bullets to the lead industry and deaths from chemical explosives to chemical fuel cells. An analysis of how the Jacobson paper is dishonest and biased.

US would $2+ trillion over decades to upgrade the energy grid.

A presentation discussing the costs and reserve requirements for higher percentage wind

EWEA (European wind Association, obviously pro-wind) presented a plan to get to 30% wind power by building a Europe/Africa wide grid to connect wind farms. They think it will take decades to scale to that level.

Jacobson claims that an all battery-powered U.S. vehicle fleet could be charged by 73,000 to 144,000 5-megawatt wind turbines.

This is 365 to 720 nameplate Gigawatts with 20-40% capacity factor. About 500-800 TWh/year if it was scaling the current 94 GW of world wind power.

So supplying power to an all battery-powered US vehicle fleet could be done by 20-30% of existing world nuclear power instead of 550-850% of current wind power.

Nuclear power plant emissions include those due to uranium mining, enrichment, and transport and waste disposal as well as those due to construction, operation, and decommissioning of the reactors. We estimate the lifecycle emissions of new nuclear power plants as 9–70 g CO2e kWh−1, with the lower number from an industry estimate and the upper number slightly above the average of 66 g CO2e kWh−150 from a review of 103 new and old lifecycle studies of nuclear energy. Three additional studies estimate mean lifecycle emissions of nuclear reactors as 59, 16–55, and 40 g CO2e kWh−1, respectively; thus, the range appears within reason.

Wind has the lowest lifecycle CO2e among the technologies considered. For the analysis, we assume that the mean annual wind speed at hub height of future turbines ranges from 7–8.5 m s−1. Wind speeds 7 m s−1 or higher are needed for the direct cost of wind to be competitive over land with that of other new electric power sources.33 About 13% of land outside of Antarctica has such wind speeds at 80 m (Table 2), and the average wind speed over land at 80 m worldwide in locations where the mean wind speed is 7 m s−1 or higher is 8.4 m s−1.23 The capacity factor of a 5 MW turbine with a 126 m diameter rotor in 7–8.5 m s−1 wind speeds is 0.294–0.425 (ESI), which encompasses the measured capacity factors, 0.33–0.35, of all wind farms installed in the US between 2004–2007.26 As such, this wind speed range is the relevant range for considering the large-scale deployment of wind. The energy required to manufacture, install, operate, and scrap a 600 kW wind turbine has been calculated to be 4.3 × 106 kWh per installed MW.37 For a 5 MW turbine operating over a lifetime of 30 yr under the wind-speed conditions given, and assuming carbon emissions based on that of the average US electrical grid, the resulting emissions from the turbine are 2.8–7.4 g CO2e kWh−1 and the energy payback time is 1.6 months (at 8.5 m s−1) to 4.3 months (at 7 m s−1). Even under a 20 yr lifetime, the emissions are 4.2–11.1 g CO2e kWh−1, lower than those of all other energy sources considered here. Given that many turbines from the 1970s still operate today, a 30 yr lifetime is more realistic.

So the nuclear industry CO2 figure is in the middle of the lifetime wind CO2 emissions figure.

New laser enrichment methods would reduce the energy used by 3-20 times which would could reduce the energy and thus the CO2 emitted by nuclear power.

Jacobson has some penalty for delays and war/terrorism. This is total BS as people can and do make nuclear weapons without leveraging the enrichment or facilities for nuclear power. This part of his analysis is junk.

For nuclear energy, we add, in the high case, the potential death rate due to a nuclear exchange, as described in Section 4d, which could kill up to 16.7 million people. Dividing this number by 30 yr and the ratio of the US to world population today (302 million : 6.602 billion) gives an upper limit to deaths scaled to US population of 25500 yr−1 attributable to nuclear energy. We do not add deaths to the low estimate, since we assume the low probability of a nuclear exchange is zero.

As noted nuclear power generation is not connected with nuclear weapons. Countries have almost always gotten nuclear weapons first and then gotten nuclear power. Plus the US has thousands of nuclear weapons now and if nuclear power is increased ten times or one thousand times that is independent of those nuclear weapons.

Proposed: Interconnecting geographically-dispersed intermittent energy sources
Interconnecting geographically-disperse wind, solar, tidal, or wave farms to a common transmission grid smoothes out electricity supply significantly, as demonstrated for wind in early work.105 For wind, interconnection over regions as small as a few hundred kilometers apart can eliminate hours of zero power, accumulated over all wind farms and can convert a Rayleigh wind speed frequency distribution into a narrower Gaussian distribution.106 When 13–19 geographically-disperse wind sites in the Midwest, over a region 850 km × 850 km, were hypothetically interconnected, an average of 33% and a maximum of 47% of yearly-averaged wind power was calculated to be usable as baseload electric power at the same reliability as a coal-fired power plant.107 That study also found that interconnecting 19 wind farms through the transmission grid allowed the long-distance portion of capacity to be reduced, for example, by 20% with only a 1.6% loss in energy. With one wind farm, on the other hand, a 20% reduction in long-distance transmission caused a 9.8% loss in electric power. The benefit of interconnecting wind farms can be seen further from real-time minute-by-minute combined output from 81% of Spain's wind farms. Such figures show that interconnecting nearly eliminates intermittency on times scales of hours and less, smoothing out the electricity supply. In sum, to improve the efficiency of intermittent electric power sources, an organized and interconnected transmission system is needed. Ideally, fast wind sites would be identified in advance and the farms would be developed simultaneously with an updated interconnected transmission system. The same concept applies to other intermittent electric power sources, such as solar PV and CSP. Because improving the grid requires time and expense, planning for it should be done carefully.

Rebuilding and upgrading the grid to allow for this is a long term and expensive process. The Jacobson report does not count this against wind or solar. The various approaches to addressing intermittency would not work that well and it assumes that there is enough wind and renewables deployed to make it work. ie Spend a few trillion to build it and it will work.

The land area calculations are also biased.

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