Power storage to change the world
The problem with solar and wind generation is that power is needed 24/7, especially at night.
According to Hackett: “In some countries, we are now seeing
periods in which the levels of re- newable-energy generation are exceeding total grid energy de- mand during solar or wind strength peaks.
“(But) when clouds occlude solar-panel or CSP arrays, their energy output can fall away so fast that baseload power generators may not be able to be spun up fast enough to fill the gap.
“This leads to pathological out- comes, such as the need to burn more coal in parallel to operating renewables, just in case clouds move rapidly across the sun.”
The answer, obviously, is stor- age. Grid-scale batteries can re- place the need for peak generation — hydro and gas turbines, or larg- er coal generators, would then be needed for just average usage.
Musk’s presentation launching Tesla’s Powerwalls and Power- packs goes a step further, propos- ing batteries as a means for making a complete transition to sustainable energy.
“With the 160 million Power- packs you can transition the Unit- ed States. With 900 million you can transition the world,” Musk says.
“You can basically make all electricity generation in the world renewable and primarily solar, it will be so. And then, going a little further, if you want to transition all transport and all electricity generation and all heating to re- newable you need approximately two billion Powerpacks.”
YOU HAVE to hand it to Elon Musk for his ability to change the game and capture the headlines. The billionaire entrepreneur made a fortune from the sale of PayPal, then went on to challenge luxury carmakers with the Tesla Model S, and to shock the satellite-launcher establishment with SpaceX’s cut-price Falcon 9 rockets. Mr Musk now wants to disrupt the electricity business—by changing the way people consume the stuff, preferably by generating and storing their own, and kissing the grid goodbye.
On April 30th, Tesla unveiled a line of lithium-ion storage batteries (similar to those used in its electric cars) that let homeowners and businesses save surplus electricity produced by rooftop photovoltaic panels during the day for use at night.
Tesla reckons up to nine Powerwalls can be hooked together for a total of 90kWh. Beyond that, customers will be able to order (later this year) a commercial version of the battery system, called Powerpack. This will have a capacity of 100kWh, and cost a reputed $25,000. Powerpacks can be plugged together to provide up to ten megawatt-hours (MWh) of storage. Amazon is installing 4.8MWh of the units in one of its data centres in northern California. Target, a national retail chain, has a similar trial underway.