Several energy analysts who are pro-solar and wind believe that they will dominate global energy and not face limitations based upon grid issues and other factors The pro-solar case is based upon massive scaling of lower cost solar and low cost batteries.
In the USA, the residential solar market is starting to slow down after years of high double-digit gains—on average, the market has grown more than 50% every year in the past four years. But as the market becomes more saturated, it’s not the same high growth of a new industry, said Nicole Litvak, an analyst with GTM Research. She expects growth of around 10% to 15% in the coming years.
India plans to add 12 GW solar power, 4 GW wind energy, 500 MW biomass-based power and 225 MW small hydro power capacity between April 2016 and March 2017. Between April and September 2016, India managed to add only 3.2 GW of grid-connected renewable energy capacity compared to the full year target of 16.6 GW. India plans to have an installed solar power capacity of 100 GW and wind energy capacity of 60 GW by March 2022.
In order for solar and wind to surpass hydro then India would have to surpass hydro the target for solar by about ten times and for China to match that as well. 100GW of solar is about 100 TWh. Solar and wind need to get an additional 2000 TWh beyond the growth projected by the IEA.
Elon says there needs to be 200,000GWh of batteries to make the world go solar. This would need about 300-900 gigafactory battery factories to produce the required batteries in about 40 years.
China is cutting subsidies to wind by 15% and solar by 19% in 2017 The move comes as average solar panel prices have tumbled about 30 percent this year, according to data from Bloomberg New Energy Finance, resulting in a lowering of the bids that solar developers offer to build projects. China will also encourage local authorities to continue making use of auctions to select renewable energy developers, in order to further lower power prices
About 1000 Terawatt hours of Hydro power was added over the last ten years. This is more than the total wind and solar power generation. Hydro will still add 500 Terawatt hours over the next 5 years.
Wind and solar power combined is still less than one third the hydro power generation. The projection is that worldwide wind and solar power combined will be about half of hydro power generation in 2021.