It's always just been another excuse to keep the economic status quo. We've had all the technology we need for a long time to solve emissions. We're not waiting on any battery tech breakthrough that can sustain a renewable grid, hydroelectric has been doing it this whole time. Motor pumps water uphill, water turns generator when it goes downhill, congratulations you have stored renewable energy with water and a hill. Use pulleys and weights, use tanks and air pressure, whatever you want, it just has to be built. There's no missing link here, it's just boring and doesnt have much opportunity for tech startup investment.