Close to 80% of the world's energy supply could be met by solar power and other forms of renewable energy by mid-century if deployment is backed by the right enabling public policies, according to a new report from researchers working with the Intergovernmental Panel on Climate Change (IPCC).
The findings also indicate that the rising penetration of renewable energies could lead to cumulative greenhouse gas savings equivalent to 220 to 560 gigatonnes of carbon dioxide between 2010 and 2050. The upper end of the scenarios assessed, representing a cut of around one-third in greenhouse gas emissions from business-as-usual projections, could assist in keeping concentrations of greenhouse gases at 450 parts per million.
This change could contribute toward a goal of holding the increase in global temperature below 2 degrees C – an aim recognized in the United Nations Climate Convention's Cancun Agreements.
‘The report shows that it is not the availability of the resource, but the public policies that will either expand or constrain renewable energy development over the coming decades,’ says Ramon Pichs, co-chair of Working Group III. ‘Developing countries have an important stake in this future: This is where most of the 1.4 billion people without access to electricity live, yet also where some of the best conditions exist for renewable energy deployment.’
The six renewable energy technologies reviewed in the report are bioenergy, direct solar energy (including photovoltaics and concentrating solar power), geothermal energy, hydropower, ocean energy and wind energy. More than 160 existing scientific scenarios on the possible penetration of renewables by 2050, alongside environmental and social implications, were reviewed, with four analyzed in depth, the IPCC says.
Although the scenarios arrive at a range of estimates, the overall conclusions are that renewables will take an increasing slice of the energy market. The most optimistic of the four in-depth scenarios projects renewable energy accounting for as much as 77% of the world's energy demand by 2050 – up from just under 13% of the total primary energy supply in 2008.
The report concludes that although the proportion of renewable energy will likely increase even without enabling policies, past experience has shown that the largest increases come with concerted policy efforts. For instance, if environmental impacts such as emissions of pollutants and greenhouse gases were monetized and included in energy prices, more renewable energy technologies may become economically attractive.
Currently, direct solar contributes only a fraction of 1% to total global energy supply, the report adds. Potential deployment scenarios range from a marginal role of direct solar energy in 2050 to one of the major sources of energy supply. The actual deployment will depend on continued innovation, cost reductions and supportive public policies.
The full report is expected to be made available here after May 31.