In the face of mounting global warming, solar power is in a unique position to cut global greenhouse gas (GHG) emissions while simultaneously meeting the energy demands of a growing population. In line with the Sustainable Development Goals (SDGs), solar power can help bring light and power to more than one billion people worldwide that currently live in poverty and without access to electricity. Indeed, the International Energy Agency (IEA) projects that by 2050 solar electricity could account for up to 20 to 25% of global electricity production.

Last year, the Massachusetts Institute of Technology (MIT) published a report on the future of solar energy through its Energy Initiative, a hub for energy research, education and outreach. The study is the latest in MIT’s ‘Future Of’ series and sheds light on a range of complex and important issues involving solar energy and the environment.

Though recent years have seen a rapid growth in installed solar capacity and advances in innovation, efficiency, and cost, additional improvements are still required for solar power to take off. The report identifies critical measures for accelerating the innovation and deployment of solar power. Two are below:

      I.         Among the different solar technologies, crystalline silicon (c-Si) is the most mature and cost-competitive. Though improvements are still being pursued by businesses and technology developers, the limitations of c-Si have led to research into thin-film PV alternatives. These technologies have the potential to provide superior performance while also being based on environmentally benign and earth-abundant materials. A greater share of public funding should target these technologies.


     II.         Established grid networks are not designed to handle large shares of renewable energy generation, especially when power also flows from customers and decentralised settings back to the network. This identifies a self-limiting aspect of solar power: high levels of penetration may lead to increased operating costs and even to problems maintaining grid reliability. This highlights the importance of developing smart grids and energy storage technologies as part of an integrated strategy for achieving economical large-scale PV deployment.

As the graph below indicates, solar power has declined rapidly in cost - from $76 per watt in 1977 to $0.74 per watt in 2013. Though solar energy is currently already competitive with dirty sources of energy in some parts of the world, a few more years of innovation and cost reduction will lead to solar being too cheap and competitive to ignore. Even the SunShot Initiative by the U.S. Department of Energy (DoE), which seeks to make solar energy cost-competitive with other forms of electricity by the end of the decade, projects futures in which the cost of solar technologies decrease by 75% between 2010 and 2020.



Despite this sharp decline in the cost of solar energy, major scale-ups in the decades to come will depend on the solar industry’s ability to overcome several hurdles, including cost and the availability of novel technologies. A key conclusion of the MIT report is that without government policies to help overcome these challenges, through a price on carbon emissions, for example, it is likely that solar energy will continue to supply only a small percentage of the world’s electricity needs. Without a carbon price, the cost of reducing emissions and achieving the SDGs will be higher. The bottom line: widespread solar energy requires entrepreneurs and innovators, but also action from policymakers. 

Julian Payne is a Project Officer for Research and Policy at SDSN Youth. All opinions expressed on the blog are the opinion of the authors and not of SDSN Youth.