Combined with technology advances and an increase in polysilicon supply the costs of solar photovoltaic (PV) cells will decrease rapidly—by more than 40 percent in the next three years, according to a new assessment by the Worldwatch Institute in Washington, D.C., and the Prometheus Institute in Cambridge, Massachusetts.
According to the report global production of solar photovoltaic (PV) cells has risen sixfold since 2000 and grew 41% in 2006 alone. Although grid-connected solar capacity still provides less than 1 percent of the world's electricity, it increased nearly 50 percent in 2006, to 5,000 megawatts, propelled by booming markets in Germany and Japan.
Some further excerpts from the report:
This growth has been constrained by a shortage of manufacturing capacity for purified polysilicon, the same material that goes into semiconductor chips. But the situation will be reversed in the next two years as more than a dozen companies in Europe, China, Japan, and the United States bring on unprecedented levels of production capacity. In 2006, for the first time, more than half the world's polysilicon was used to produce solar PV cells.
“Solar energy is the world’s most plentiful energy resource, and the challenge has been tapping it cost-effectively and efficiently,” says Janet Sawin, a senior researcher at Worldwatch, who authored the update. “We are now seeing two major trends that will accelerate the growth of PV: the development of advanced technologies, and the emergence of China as a low-cost producer.”
The biggest surprise in 2006 was the dramatic growth in PV production in China. Last year, China passed the United States to become the world’s third largest producer of the cells—trailing only Germany and Japan.
"To say that Chinese PV producers plan to expand production rapidly in the year ahead would be an understatement,” says Travis Bradford, president of the Prometheus Institute. “They have raised billions from international IPOs to build capacity and increase scale with the goal of driving down costs. Four Chinese IPOs are expected to come to market this month alone."
In the meantime, supply shortages have led manufacturers to find ways to use polysilicon more efficiently, and have accelerated the introduction of new technologies that do not rely on purified silicon and are inherently less expensive to manufacture. So-called thin film cells can be made from amorphous silicon and other low-cost materials, and companies developing these technologies have recently become the darlings of Silicon Valley venture capitalists.
Although in the past, thin film cells have not been efficient enough to compete with conventional cells, today over a dozen companies—including Miasole, Nanosolar, and Ovonics—are competing to scale up production of low-cost solar modules that can be churned out like rolls of plastic.
"The conventional energy industry will be surprised by how quickly solar PV becomes mainstream—cheap enough to provide carbon-free electricity on rooftops, while also meeting the energy needs of hundreds of millions of poor people who currently lack electricity," Sawin says.
This assessment confirms what has been reported in The Energy Blog over the past two years, that in about three years, in 2010, costs of PV solar will start to come down significantly as silicon supply increases and thin film suppliers start to undercut silicon PV costs. While this market will be large and supplement baseload power during the daylight hours, it will not be until energy storage technologies, such as flow batteries, become more economical, extending the usefulness of solar for a few hours, to the end of peak power demand, that PV solar can become mainstream. Until that time solar thermal, for which energy storage is becoming developed, should remain the main source of utility power. Until then PV solar will be limited, for the most part, to areas that offer substantial subsidies. During this time concentrating PV solar power has a good chance of becoming the lowest cost supplier of distributed power. If PV solar meets cost expectations, it should eventually become the dominant source of solar power. The role of solar power, after that, will only be limited by the costs of distribution of the power.
Solar power supplemented by wind power and ocean power, both with energy storage; and geothermal power and hydro-power then would be capable of suppling all our power needs. However until that time we must depend on coal power, hopefully with carbon sequestration, and nuclear power for the majority of our power production. Although conservation of power should become a major component of our energy usage, this probably will only happen in a big way when the cost of power becomes much higher than it is now.