First the good news. Solar power could account for nearly a quarter of the world’s electricity by 2050 according to two reports issued this week by the International Energy Agency.
The bad news is that the overwhelming bulk of that electricity will be produced by large centralised power plants. Off-grid solar photovoltaic electricity, though important in remote areas and developing countries, will account for little more than one per cent of global electricity production predicts the IEA.
The two reports or ‘roadmaps’, on solar photovoltaic (PV) and concentrating solar power (CSP), attempt to describe the growth path for each technology from today to 2050. They identify technology, financing, policy and public engagement milestones that need to be achieved to realise their full potential.
“The combination of solar photovoltaics and concentrating solar power offers considerable prospects for enhancing energy security while reducing energy-related CO2 emissions by almost six billion tonnes per year by 2050,” said IEA, executive director Nobuo Tanaka at the launch of the two reports in Valencia, Spain.
PV and CSP are complementary
He argued that solar PV and CSP are complementary rather than competing technolgies. “The firm capacity and flexibility of CSP plants will help grid operators integrate larger amounts of variable renewable electricity such as solar PV and wind power. PV will expand under a broader range of climate conditions and bring clean renewable electricity directly to end-users.
Although superficially similar, the technologies work on very different principles. ‘Solar photovoltaic’ converts sunlight directly through chemical reaction into electricity while concentrated solar power uses heat from the sun to boil water which is then used to generate power.
The PV report says that global capacity has been increasing at about 40% a year since 2000. It estimates that with effective policies in place, PV on residential and commercial buildings will achieve grid parity by 2020 in many regions and will become competitive at utility-scale in the sunniest regions by 2030, providing 5% of global electricity. By 2050, it will provide around 11% of global electricity production (4 500 TWh per year) saving 2.3 gigatonnes (Gt) of CO2 emissions a year.
Solar PV rollout needs Government support
But PV will only reach this level with considerable support from governments. And as it matures, grid integration and management and energy storage will become key issues, argues the report. “The PV industry, grid operators and utilities will need to develop new technologies and strategies to integrate large amounts of PV into flexible, efficient and smart grids,” it says.
The report or road map provides a fascinating insight into the development of PV around the world. In particular it highlights how slow the US has been in adopting PV. It says that a handful of countries with strong policy regimes account now for 80% of global installed PV.
US lagging in solar
Germany currently accounts for 36 per cent, Spain 22%, Japan 15% and the US which is a far larger economy than any of them, accounts for just 8 per cent of capacity.
This was backed up by a report this week in the New York Times, which claimed that in Los Angeles, the nation’s eighth sunniest city, only 1,627 homes boast solar power.
In its second report, the IEA described CSP as “an emerging technology”. Unlike PV which only needs daylight, CSP needs sunshine and clear skies. One of its great advantages is that heat can be easily stored meaning that CSP can generate electricity during times of peak demand –at night.
It says that By 2050, with appropriate support, CSP could provide 11 .3% of
global electricity. The report predicts that within twenty years CSP will be able to compete with coal plants that emit high levels of CO2. In the medium-to longer term, concentrating solar facilities can also produce hydrogen, which can be blended with natural gas, and provide low-carbon liquid fuels for transport and other end-use sectors.
The roadmap says that North America is currently the largest producing and consuming region for CSP electricity, with a third of global capacity, followed by Africa, India and the Middle East. Northern Africa.