People pass painted barrels on their way to a demonstration to commemorate the anniversary of the earthquake and nuclear disaster of Fukushima one year ago, near Salzgitter, Germany, on March 11, 2012. (Jens Meyer/AP)

In a country with ambitious intentions to go green, last week brought an unsettling image for eco-advocates: Germany’s environment minister presiding over the opening of one of the largest coal-fired power plants in the world.

The massive new power station near Cologne is a frontal challenge to efforts to drive down greenhouse gases, and some critics say it embodies a tricky contradiction in Germany’s ambitions to reduce emissions by 40 percent by 2020 and eliminate nuclear power two years later.

A year after German Chancellor Angela Merkel made a surprise decision to speed her country’s phaseout of nuclear power, environmentalists who hailed her plan — a reversal of her previous positions — now worry that her center-right Christian Democrats are too quick to embrace dirtier alternatives.

Germany’s dilemma shows how difficult it is to balance competing environmental priorities, even with vast resources and popular support for the efforts, analysts say. With low-emission nuclear power falling into disfavor in many countries after Japan’s Fukushima Daiichi nuclear meltdown, others may soon have to confront the same questions.

German leaders say that they are finding the right compromise between cost and environmental stewardship and that they will meet their 2020 goals.

In Germany, replacing nuclear power by 2022 (The Washington Post/Sources: German Association of Energy and Water Industries; German Environment Ministry)

“For many years, we will need conventional fossil energy in addition to renewables,” German Environment Minister Peter Altmaier said in an interview. “For 2020, the aim is to have 35 percent renewables, but that means 65 percent fossil electricity.”

He added: “We have to implement two goals at a time, and this can create some problems in the beginning. But we are working very hard, and I am very optimistic that Germany can manage to meet its ambitious CO2 aims as well as its aims to eliminate its nuclear power.”

The lignite-fired power plant that opened last week may be the embodiment of an environmentalist nightmare. Soft lignite coal is one of the worst offenders for greenhouse gas emissions, although the new plant is replacing older, less-efficient ones. Nuclear power is politically unpopular in Germany, but it is a relatively low-emission source of electricity, meaning that the country has to fill the gap with dirtier sources as renewable energy struggles to keep pace.

Environmentalists fret that Merkel’s allies simply aren’t taking the goals seriously enough. Just months before the Fukushima meltdown in Japan, Merkel moved to postpone the nuclear phaseout as a component of plans to reduce greenhouse emissions in Germany. After the March 2011 earthquake and tsunami caused the nuclear meltdown, Merkel yielded to popular pressure and reverted to the speedier nuclear phaseout planned by her predecessor, center-left Social Democrat Gerhard Schroeder.

But Merkel’s opponents aren’t sure that she really has won the support of her sometimes-fractious coalition.

“They are not convinced” that the nuclear phaseout makes sense, said Oliver Krischer, a member of the opposition Greens in the German parliament and the party’s speaker on energy policy. “They still believe in the old system and aren’t doing the necessary steps which follow the stopping of the nuclear power plants.”

The obstacles

With wind and solar energy generating a growing portion of Germany’s electricity, the country is in the forefront of attempts to master the difficulties associated with renewable power. Most conventional energy sources feed a steady stream of electricity into the grid, but the output from windmills and solar panels fluctuates widely, depending on the sunniness or windiness of the day.

Storing electricity on a large scale remains a major technical challenge, and Germany’s transmission system isn’t set up to deal with intermittent renewable energy. The German Federation of Industrial Energy and Power, an association of commercial power consumers, has been critical of the country’s environmental plans, and the federation says that power disruptions have increased 30 percent in the past three years, a problem that threatens sensitive industrial equipment.

Germany is trying to overcome such obstacles. Along the way, the country, already an industrial powerhouse, could become a major exporter of the smart-grid equipment needed to produce and distribute large-scale renewable energy, leaders say. But the scale of the endeavor is enormous. Altmaier, the environment minister, has called it the greatest economic challenge since the reconstruction of Germany after World War II. Others caution against expectations that it will happen quickly.

“This is probably the most ambitious industrial project we’ve ever had, and it will not happen overnight,” said Felix Christian Matthes, an energy expert at the Institute for Applied Ecology in Berlin.

The transition

In the meantime, policymakers say, the nation needs backup from conventional power sources for windless days, as well as cloudy ones, of which there are many during Germany’s long, dreary winters.

So far, that backup seems likely to come from coal-fired plants, causing an uproar among environmentalists. The major alternative, natural gas, is cleaner, but it is currently far more expensive in Europe, leading energy companies to shy away from investing in it.

“Gas-fired power plants are too expensive, and this is really a problem,” said Claudia Kemfert, an expert on the economics of energy at the German Institute for Economic Research. “It’s a concern if you’re really looking for an energy turnaround. Coal power plants are not really sustainable.”

Despite all the complications, many experts expect Germany to meet its energy goals. But they concede that reducing energy consumption by 10 percent by 2020 — another component of Germany’s eco-friendly plans — might be a tough target.

The use of solar energy is growing in Germany, in part, because of a boom fueled by subsidies that makes installing solar panels highly profitable.

Those costs are passed on to consumers, who may have to pay an additional $154 per household on average next year as a result. Consumer groups estimate that electricity costs could surge 20 to 60 percent in the next decade as a result of the efforts to promote green energy.

Rising electricity bills are a problem for low-income families, critics say, but the energy plans, nonetheless, are widely popular in Germany, where the issue is framed as a moral imperative more often than an economic one.

Looking further into the future, increasing the share of renewable energy to 80 percent by 2050 is a tough target, experts say, because it will require a more fundamental change in the production, transmission and use of electricity.

“The real energy transition is starting in 2025, because then it’ll really become harder and harder,” Kemfert said.

Petra Krischok contributed to this report.