The technology is improving all the time. it is now possible to store renewable energy in much greater amounts than it was in 2015.
I am sorry I don't know how to do links but the following is a small quote from the website www.sciencedirect.com
"Contemporary technologies include pumped hydro storage (PHS), compressed air energy storage (CAES), fuel cells and hydrogen storage (FC-HS), flywheels, supercapacitors (SCs), superconducting magnetic energy storage (SMES) and various battery systems."
This is where our country could start to be world leaders in this technology, if we just grasp the chance. otherwise we will end up buying renewable energy from other countries who have put much more investment into storage solutions.
We have the brainpower and science in this country, we just need to have confidence and be forward looking.
Nuclear power is yesterdays solution.