It's helpful to have two flavors of storage; one short term and efficient (batteries), one long term with low capex (hydrogen, thermal). The last is the most undeveloped but there are promising ideas.
It's helpful to have two flavors of storage; one short term and efficient (batteries), one long term with low capex (hydrogen, thermal). The last is the most undeveloped but there are promising ideas.
I put some numbers into this, and the required power for long term storage is significantly lower than I'd have expected.
This was giving me for Germany (assuming 80GW of constant demand) under 50GW of required hydrogen turbine power (35GW of gas turbines are already installed, but only a fraction H2 ready).
Overprovisioning (wind/solar) is suprisingly high, with 180GW of wind and 440GW of solar. Currently installed capacity for those is about 30% of that.
Short-term storage capacity is a really big gap though (the model suggests 750GWh, and currently there's <30GWh installed).
In conclusion: Under pessimistic simplifications, Germany is at about 30% progress toward fully renewable electricity (but battery capacity is lagging behind).
Assuming wind/solar buildout continues at rates comparable to the last decade, this would mean zero-emission electricity in ~35 years. Could be worse. But I'm personally bracing for 2-4°C of warming, and don't think european glaciers will survive the next century...
If wind and PV have similar levelized cost of energy (LCoE), then the solution will use the lack of correlation between the two to avoid much storage. In this case, long term storage is over period of the variability of wind, which might be weeks.
But if PV is significantly cheaper than wind -- and this is where trends are going -- then long term storage becomes more for seasonal leveling, at least at high latitudes.
There's still a large place for short term storage, and economics is still strongly affected by the cost of that storage. So it's great news batteries have become so cheap to produce.