The ‘duck curve’ is solar energy’s greatest challenge

The ‘duck curve’ is solar energy’s greatest challenge


When you flip a light switch, you expect it
to work right? All of your appliances work, because your
power company has electricity ready to transmit. For a lot of customers. And utility companies have gotten really good
at anticipating that demand. But a rise in solar energy production is making
their jobs a bit more complex. Here’s a chart that explains why. It’s showing demand for electricity at any
given time of day. The power companies supply the least amount
of power overnight. Then, it ramps up in the morning. Everyone’s woken up and business gets going. Then at sunset, energy demand peaks. Utility companies will update models like
this to operate as efficiently as possible. But the introduction of renewable energy,
particularly the solar energy, has started causing problems in these demand curves. In 2010, solar panel deployment really started
taking off. Most of those installations took place in
California, so researchers there started looking into it. They found that the sun produces the most
energy at mid-day. And when you factor in that new mid-day production,
your demand curve changes like this. Every year means new solar capacity, which
makes mid-day demand dip lower and lower. Researchers call this drop in demand the “duck
curve.” From the grid managers’ perspective, the people
whose job it is to constantly balance generation and demand, it looks like a drop in demand. That drop in demand creates two problems. The first has to do with the intense ramps
in the new chart. As the sun sets, solar energy production ends
just as the demand for energy typically peaks. Power plants then have to rapidly ramp up
production to compensate for that. Which is kind of hard to do with the current
fleet of power infrastructure. The second problem is economic. Say you have a couple of nuclear and coal
plants. Those plants are only economic when they are
running all the time, basically. They run around the clock. And if you have to turn them off at mid-day,
it completely screws up their economics and plus lots of utilities just have contracts
with those power plants to keep them running all the time. So that creates sort of an artificial floor. If solar generates too much power and there’s
no use for it, there’s no one to consume it, then grid managers just have to turn some
solar panels off. If they didn’t, we could risk overloading
or even damaging the power grid. So we throw away some of that extra solar
energy. Effectively, what’s happening is that solar
power is being wasted. That waste, curtailment, is the big challenge
moving forward for solar energy. If you want solar, eventually to power everything
or close to everything, you’ve gotta figure out some way of shifting it to the night time. Cause the sun’s down during the night time. The more power that can be stored, the more
you can sort of let solar rip. While the grid managers figure out how to
serve this new supply and demand, this duck is the greatest challenge facing renewable
energy. Thank you for watching and thanks for Principal
Financial for sponsoring Vox Video. Whether it’s securing investment, retirement,
or protecting your insurance assets, they can help you prepare for the unexpected.