The UK's National Grid faces an increasing challenge to keep generation at its most efficient, due to the increasing variability of power sources. It needs to find new ways to store surplus energy, in order to meet peaks in demand. Read on for a fascinating, data-rich insight into the challenges of powering your computers, kettles, TVs and EVs.
Recently, Robert Llewellyn (yes, that one) spoke to Nigel Williams from the UK's National Grid in this a fascinating 11-minute video (embedded below). This is no fluffy, dumbed-down puff-interview: there's some great data here.
To quote YouTube commentator betterspud21:
It's really pleasing that you found someone so knowledgeable to interview, who clearly seems excited and open-minded to...changes the future brings.
As Williams points out, power generation is at its most efficient when there's no spikes in demand. The closer the demand curve is to being flat, throughout the day and night, the more efficiently power stations can run, and the easier it is for the Grid to choose the most inexpensive sources of power available from moment-to-moment.
However, in reality, there are always peaks and troughs in demand. The most notable trough is what's sometimes referred to as "the bathtub" -- a sharp reduction in electricity demand overnight. This challenge, plus the challenge caused by the variability of some renewable sources, means that the Grid needs new ways to store energy (hence: "filling the bathtub").
Today, that storage is done at four huge hydro-electric sites in Scotland and Wales, where off-peak, surplus electricity is used to pump water uphill, into reservoirs. This water can then be released into downhill reservoirs, via turbines, to generate instant power to meet demand (e.g., when Eastenders ends).
And that's going to get more important in the future. Williams expects wind-energy generating capacity to grow from today's 5 GW to 30 GW in 2020.
Llewellyn's big interest here is electric vehicles (EVs), and Williams exposes the common canard that EVs will somehow melt the grid if they become popular. He says their forecast is for 500,000 such vehicles in 2020, which would cause a peak demand of just 1GW -- a metaphorical drop in the ocean.
Richi Jennings, editor of Input Output UK, is also an independent analyst, specializing in blogging, email, spam, security, and other technology topics. His writing has won ASBPE and Neal awards. You can encircle him at +richi, follow him as @richi on Twitter, pretend to be his friend at Facebook.com/richij or just use boring old email: firstname.lastname@example.org.