ANALYSIS: Nuclear Moratorium in Germany Could Cause Spike in CO2 Emissions

By Sara Mansur, cross-posted from the Breakthrough Blog

Carbon dioxide emissions in Germany may increase by 4 percent annually in response to a moratorium on seven of the country's oldest nuclear power plants, as power generation is shifted from nuclear power, a zero carbon source, to the other carbon-intensive energy sources that currently make up the country's energy supply.

The German government announced today that it will shut down seven of the country's seventeen nuclear power plants for an indefinite period, a decision taken in response to widespread protests and a German public increasingly fearful of nuclear power after a nuclear emergency in Japan. The decision places a moratorium on a law that would extend the lifespan of these plants, and is uncharacteristic of Angela Merkel, whose government previously overturned its predecessor's decision to phase nuclear out of Germany's energy supply.

The seven plants, each built before 1980, represent 30% of Germany's nuclear electricity generation and 24% of its gross installed nuclear capacity. Shutting down these plants, or even just placing an indefinite hold on their operation, would be a major loss of zero-emissions generation capacity for Germany. The country currently relies on nuclear power from its seventeen nuclear power plants for about a quarter of its electricity supply.

The long-term closure of these plants would therefore seriously challenge Germany's carbon emissions efforts, as they try to meet the goal of 40% reduction below 1990 carbon emissions rates by 2020.

The moratorium could cause a spike in CO2 emissions as Germany turns to its other, more carbon-intensive sources to supply its energy demand. Already, the country has been engaged in a "dash for coal", building dozens of new coal plants in response to the perverse incentives and intense lobbying from the coal industries made possible by the European Emissions Trading Scheme. (As previously reported by Breakthrough Europe).

Below, we've projected three possible scenarios for the country to make up for this lost generation- through either entirely coal-fired power plants, entirely natural gas power plants, or an equal split of both. Across each of these cases, we find that total carbon dioxide emissions would increase annually by at least 17 million tons, a 2% increase in the country's overall emissions.

And, if lost generation were made up for entirely by coal-fired plants, carbon emissions would increase annually by as much as 33 million tons. This would represent an overall 4% annual increase in carbon emissions for the country and an 8% increase in carbon emissions for the power sector alone.

See Chart 1 at the end of this post for exact numbers for each scenario.

Alternatively, should the country try to replace lost generation entirely with power from renewables, it would need to more than double generation of renewable energy, from where it currently stands at 97 billion kWh to about 237 billion kWh. As part of the country's low-carbon strategy, Germany has planned to deploy at least 20% renewable energy sources by 2020. If the nation now chooses to meet this goal by displacing nuclear plants, 2020 emissions levels would be higher than had the country otherwise phased out its carbon-intensive coal or natural gas plants.

As public concern about nuclear power rises and pressure is placed on politicians to shut down and phase out the current fleet of nuclear power plants in nations like Germany, the challenge of rapidly reducing global warming-inducing greenhouse gases increases. With some time before we know the potential effects of Japan's nuclear catastrophe, this much is clear:

"The cost of fighting against global warming will increase, that is sure," [IEA chief Nobuo Tanaka] told Reuters. "I think it is very difficult (to fight global warming), even impossible, without using nuclear power."
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*Carbon emissions factors used are those estimated by the World Bank in 2009 for new coal-fired power plants (0.795 t C02/MWh) and new gas-fired power plants (0.398 t C02/MWh)
**Data from Carbon Monitoring For Action, European Nuclear Society Data, and US Energy Information Administration