Monday, July 30, 2012

The Growing Potential of Solar Energy

Solar power could play a central role in Switzerland’s future energy mix by partially replacing nuclear energy which will be phased out in future. The solar industry has requested more subsidies to fund accelerated expansion.
Mounting photovoltaic panels on anti-avalanche
infrastructure in canton Valais (Keystone)

The Swiss parliament decided in 2011 against the construction of new nuclear power plants in the wake of the Fukushima nuclear disaster in Japan and a wider shift away from atomic power.
In the coming months Switzerland’s new energy policy must be fine-tuned and agreement found on the substance and framework of how to exit nuclear energy.

At stake is how this can be achieved, finding potential energy saving mechanisms to cushion the blow and financing the exit from nuclear power.

“The electricity market will adjust to the new conditions. This is not an issue. If the conditions are clear and reliable, the industry can make the necessary investments and utility companies can align their strategies,” Thomas Zwald, head of public affairs at the Swiss Association of Electricity Companies, told swissinfo.ch

Nuclear substitute

As an interim solution, the electricity industry has its sights set on gas-fired plants, but the questionable environmental credentials of this energy source have placed doubts on its acceptance as a long-term answer.

Up to now solar power has been a niche product in Switzerland, with nuclear power currently providing 40 per cent of electricity.

“With decentralised photovoltaic systems on roofs, solar energy could expand to 20 per cent [of total energy supply in Switzerland] and thus provide a substitute for half of the nuclear power now used. This does not even include the potential that large-scale plants or green areas could contribute,” according to Franz Baumgartner, professor of renewable energies at the Zurich University of Applied Sciences.

“The other half of the energy currently supplied by nuclear power plants could be made up by using a mix of wind and biomass, and later, geothermal and small hydropower plants.”

Due to their small size and widespread location, photovoltaic rooftop plants have the advantage of encountering less resistance from the population and from landscape and environmental conservationists.

This would allow them to be built faster and with less difficulty than larger gas-fired power plants, solar power plants and wind farms, which attract more controversy.

“How quickly solar power can be built up to supply 20 percent of electricity needs depends on how fast the infrastructure is developed. Over the past ten years Germany has been able to build up its proportion of new renewable energy sources to about 13 per cent. This could be taken as inspiration,” according to Baumgartner.

How far, how fast?

David Stickelberger, managing director of the Swiss Solar Energy Association, noted that some studies had optimistically pointed to a solar power expansion potential of up to 30 or 40 per cent.

“Realistically, it would be about 2025 before we could provide a share of 20 per cent,” he admitted.

Solar energy associations and electricity companies agree that the true potential of solar energy remains largely untapped. But they disagree on exactly how much solar power Switzerland could eventually produce, how quickly and at what cost.

“You need to distinguish between the technical and the economic potential,” said Zwald. “The fact is that the costs associated with solar power are still very high. Funding to subsidise the cost of feed-in tariffs needs to be increased,” said Stickelberger.

“Our model projections show that if solar power provides 20 per cent of electricity, prices would increase by about 10 per cent,” he added.

According to Zwald, the big question is whether to accelerate the transition by providing huge subsidies – as in Germany – or to wait until the price of solar energy gradually reaches market levels.

The electricity industry believes that more gas-fired power plants will have to be built to replace nuclear energy.

“It’s about how to compensate for the disappearance of energy from nuclear power plants. This path leads to gas-fired power plants because water power has a limited capacity to develop and fully compensating for the energy losses through imports is neither realistic nor politically desirable,” said Zwald.

Depending on the scenario, the companies calculate that four to eight gas-fired power plants will be needed. But gas-fired power plants burn fossil fuels that produce CO2 and are thus in conflict with Switzerland’s stated aim to reduce carbon emissions.

Plugging the gap

However, harnessing the sun’s energy also has its downsides. Unlike nuclear, water, or gas power, solar energy must grapple with the problem of irregular electricity production.

Various alternatives have been suggested to compensate for fluctuations. Because solar energy does not perform well in winter, but wind turbines do, one option would be to import wind turbine surpluses to fill the gap, from the Baltic Sea for example.

In addition, planned mega-solar power plants in North Africa and southern Spain are expected to operate year-round, potentially supplying enough power to compensate for fluctuations.

Finally, significant progress is expected in the technology of decentralised storage of solar energy, in the form of batteries, in coming years.

The decentralised production of electricity by means of photovoltaic systems will require not only an expansion of networks, but also so-called “smart grid” or “intelligent networks”. These could be precisely controlled with the help of modern communication technologies that are able to manage electricity use and consumption.

“The economy is well aware that these investments must be made and that decentralised production has gained in importance. It’s all a question of pace and how capital is applied,” said Zwald.

Private investors will need to be attracted because the expansion of renewable electricity production and the required networks will require billions.

“Whoever wants to go in a new direction needs to invest. It’s simply not possible to declare ‘we’re making an energy revolution’ without going the extra mile. You need to invest to have an edge,” said Baumgartner.

“Energy has always been a political issue. Hydropower also required a large investment initially.”

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