Recently, I did an interview with Lisa Cohn from Energy Efficiency Markets. In the interview, I explain demand response and it’s role in facilitating the integration of renewable energy:
When I wrote “Is Demand Response Clean?”, many readers thought that I was not a supporter of demand response because I pointed out that it is not necessarily clean if customers shift load to off-peak hours or use a backup generator. In fact, I am a huge advocate of demand response, but I think the focus needs to shift to how demand response facilitates the integration of renewable energy. As I mention in my interview with Lisa Cohn, without more demand response, growth in renewable energy will be much riskier:
“The biggest impact of demand response is that it is going to facilitate more integration of renewables onto the grid… California wants to get to 33% renewables by 2020. That is going to introduce a lot more risk onto the system because these are intermittent sources of power. With more demand response on the system, it is going to enable the system operator to respond to changes in weather… There are substantial automated demand response resources that are coming online… We’re in the process of trying to prove that these resources can come online in less than 10-15 seconds… If the wind stops blowing, the utility can immediately shut off a bunch of air conditioning load to respond to that reduction in generation.”
When most people in the industry think about the risk posed by renewable energy, they overlook demand response and look towards batteries and other forms of energy storage as the logical solution. A recent podcast entitled “Energy Storage: Will We Find the Holy Grail?” by Stephen Lacey of Renewable Energy World provides an example of this tendency:
“We’d all like to see a world mostly powered by renewables; the sun, wind and water providing us the energy we need to keep society moving. It’s an appealing thought, but it is possible? To some extent, with the proper integration, these resources can make up a substantial part of our energy mix. But at some point, given the variability of these resources, we have to have storage. Without it, our efforts can only go so far.”
I could say (and have said) exactly the same thing about demand response. Given the variability of renewable resources, we have to have demand response. Without it, our efforts can only go so far.
In fact, demand response and energy storage are not that different. Consider this example of two air conditioners whose owners only want them to consume renewable energy (which will be popular in the near future). One air conditioner uses a battery as backup when renewable resources are temporarily unavailable. The second air conditioner is demand response enabled and runs relatively harder when renewable resources are available and shuts off when they are not.
When renewable resources are available, the first air conditioner runs normally while extra energy is being consumed by the battery, whereas the second air conditioner consumes extra energy because it is running harder. When renewable resources are temporarily unavailable, neither air conditioner consumes grid supplied power because the first is running on the battery and the second is off. To utilities and grid operators, there is no difference between the two approaches to responding to the availability of renewable resources.
Consumers with the demand response enabled air conditioner may experience a difference in comfort on a few unusual days, but considering that many of us prefer to consume renewable energy, it may be worth the small sacrifice. After all, it is a cheaper solution than having a battery as backup.
Is energy storage the holy grail or are we overlooking other options?