[donttrustatoms]

Solar photovoltaic has dropped in cost significantly which is awesome for many applications. The problem for an individual or the grid for renewable intermittents is the consistency: the true cost is the cost not just of generation but generation plus storage (or backup).

Batteries have not had the step change in cost vs deliverable, and the question of effective and not carbon intensive recycling of batteries and most e waste remains. If solar is x cents a kWh, must add cost of storage or fossil backup generation to make sense in both terms of cost as well as carbon.

For instance, the expected cost per kWh of the Powerwall is about 35c/kWh which must be added to cost of generation and the maximum amount of time for delivering that power back at peak discharge is only a few hours. Leaves some development still to do for power in the morning after the night, or even for a cloudy day. Solar thermal has run into similar reliability problems as solar photovoltaic.