1. Fraunhofer ISE©
, Photovoltaics Report, updated, 6 June 2016, http://www.ise.fraunhofer.de
2. The Economist, Clean energy’s dirty secret: wind and solar power are disrupting electricity systems – but that’s no reason for governments to stop supporting them, 25 February 2017, http://www.economist.com
3. World Energy Outlook
, International Energy Agency, 2016
4. http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/pec_technoeconomic_analysis.pdf
5. http://www.conocophillips.com/sustainable-development/environment/climate-change/climate-change-action-plan/Pages/managing-risks-and-opportunities.aspx, accessed, 12 April 2017