The International Energy Agency (IEA) has released its Medium-Term Renewable Energy Market Report 2015 today, in which is predicts strong growth for renewable energy globally, driven by technology cost reductions. The IEA anticipates renewables accounting for two-thirds of net additions to generating capacity globally.

Adding in excess of 700 GW, renewable sources will increase share in global electricity generation from 22% in 2013 up to 26% by 2020, in what the IEA describes as a remarkable shift in a very limited period of time.

Solar looks set to play a key role in renewable deployment in this period, being the second-largest source of new capacity, behind onshore wind.

While the forecast may paint a positive picture for renewable deployment, crucially the IEA expects the renewable deployment trend to slow towards 2020, due to a range of factors. The IEA cites persistent policy and market integration uncertainties in some areas, notably Europe and Japan, along with financing challenges and integration issues in developing countries as the major constraining factors.

Because of these factors, IEA believes the level of renewable deployment in its main case forecast will fall short of what is required to effectively meet climate change goals.