The lastest issue of Nature Climate Change to reach my mailbox has some startling news, particularly considering that it comes from a generally Warmist publication. One might say is is “topsy-turvy” (upside down) from a Warmist viewpoint, but quite in keeping with a Skeptic point of view.
1) Total emissions from biodiesel are WORSE than emissions from fossil fuels, when considering both Direct and ILUC (Indirect Land Use Changes) Emissions.
2) Natural gas is WORSE than that “filthy fuel” coal when considering the net warming effects due to leakage rates of methane associated with natural gas and the cooling effects associated with aerosols from burning of coal.
3) Pure electric vehicles are WORSE than petroleum-burning hybrids, considering overall lifetime cost/benefits.
Here are some of the details:
1) A BIOFUEL CONUNDRUM. Biofuels get their energy from the Sun and absorb CO2 from the Atmosphere, making them carbon-neutral. Right? WRONG.
The graphic (from http://www.nature.com/nclimate/journal/v1/n8/fig_tab/nclimate1265_F1.html, annotations added by Ira) shows total emissions, which is the sum of Direct and ILUC (Indirect Land Use Changes) Emissions. Note that all sources of biodiesel produce more total emissions than the equivalent amount of energy derived from fossil fuels. Also note that bioethanol, while better than fossil fuels in this accounting, are far from carbon-neutral.
The orange and grey dashed lines across the bars show the threshold for a 50% and 35% emission saving, respectively, compared with fossil fuels. Initially biofuels will have to deliver a 35% saving under EU law, but this will rise to 50% in 2017. Indeed, when policymakers talk about raising the threshold in the context of the ILUC debate, they are reportedly talking about raising it to 50% — this graphic shows that according to what we know about the scale of ILUC, this policy approach wouldn’t solve the problem. ILUC data is from a draft report of the International Food Policy Research Institute; direct emissions data is from the EU’s Renewable Energy Directive, © European Union, http://eur-lex.europa.eu.
According to this research, bioethanol from wheat saves less than 50% of emissions as compared to fossil fuels. Other bioethanol sources are only about 50-60% carbon-neutral.
2. A NATURAL GAS CONUNDRUM. Natural gas (methane) produces only half the CO2 of coal per unit of energy, so it must be cleaner and greener. Right? WRONG.
According to research by Tom Wigley of NCAR [Climate Change, 108, 601-608 2011]. It turns out that burning of coal releases aerosols that have a cooling effect. Of course, that is not news to those of us familiar with the 1974 National Science Board report that warned of Global Cooling due to human-caused aerosols. In addition, it seems that up to 10% of methane, a potent “greenhouse” gas, leaks out into the Atmosphere. Leakage rates need to be kept below 2% to beat fossil fuels.
3. AN ELECTRIC CAR CONUNDRUM. Pure electric vehicles, like the Nissan Leaf and my golf cart, release no direct emissions, so they are “greener” than hybrids or conventional cars that burn gasoline or diesel. Right? WRONG.
According to research from Carnegie Mellon University [Proc. Natl. Acad. Sci., 108, 16554-16558 2011] hybrid and plug-in hybrid vehicles that burn some fossil fuels benefit society over their lifetimes more than either pure electric battery-powered vehicles or conventional gasoline-powered autos. Hybrids have smaller battery packs than pure electrics and therefore cost less to build and maintain.
… The work takes into account, for example, the power plant emissions associated with charging a plug-in car, the direct cost of oil as well as the military expense associated with defending against disruption in its supply, the impact of greenhouse-gas emissions from exhaust pipes, and vehicle recycling and land filling. …