Sydney has just hosted the Energy Storage Expo, so it's a good time to ask the question 'When is Energy Storage coming?'
It’s all about batteries, of course – how big they are, how long they last, and how much they cost. As energy retailers lower their solar feed-in rates to less than a third of what they charge for grid supply, it’s reasonable to ask whether it’s feasible to store solar or offpeak grid energy and use it later.
The good news is that lithium battery technology is improving, and now costs about $600 a kWhr. So a restaurant-sized system would cost about $26,000. That translates to a payback time of roughly 15-20 years – a bit too long for most business people.
Prices will come down in the next year or two, but some think they need to reach $120 per kWhr to appeal to the mass market. That corresponds with the 3-4 year payback times that most of us would like.
Rather than manage all this yourself, grid storage offers an easier option. Private grid managers are starting to install grid storage – a large-scale version of the same technology – to reduce peaks and so shave tariffs. They can’t afford to stay out of this business, because customers will otherwise disconnect as batteries become cheaper and easier to manage.
Storage has been just around the corner for some time, but it finally seems as if its moment has arrived.