>The variability needs to be very high to be an effective incentive for small power uses. If price of electricity goes from 10c/kWh to $1/kWh, it won't stop you

>The variability needs to be very high to be an effective incentive for small power uses. If price of electricity goes from 10c/kWh to $1/kWh, it won't stop you using 1kW kettle for 5min if you want tea. Industrial users can be persuaded to vary their usage though. A 'smart home' could also be programmed to handle variable electricity usage - e.g. load up a washing machine ready to go and let it start running when electricity is cheapest, or electric storage heaters. Neither of these things require any technological leaps whereas efficient, cost effective grid-level energy storage does.