How can the Curtailment of Electricity be Avoided?
There are several options to reduce or eventually even completely phase out curtailment measures. The feasibility of these solutions vary from country to country – depending on the national energy landscape and regulation in general and the asset base in particular – but they can be roughly grouped into the following categories:
The option that usually comes up first is the extension of the electricity grid in order to have more transport capacity for excess power. Here again, a comparison with traffic jams might be of use. If a highway is clogged all the time, city planners often come up with the solution of adding lanes to that highway. Grid operators, just like city planners, often ramp up transport capacity by expanding the existing infrastructure. Adding power lines or expanding existing ones is effective in the long run but has two drawbacks: It takes years to be implemented and it is expensive.
On-Site Storage to Avoid Loss of Energy
Another option to avoid the loss of energy that occurs when renewables infeed is curtailed is to not transport excess electricity through the power grid but to use it on-site. When electricity from a wind or solar farm cannot be sent through the grid, a battery or electrolyzer would take in the electricity and store it resp. use it to produce hydrogen. This option reduces curtailment quicker (it’s easier to install a battery or electrolyzer than to add power lines), but it also has its economic constraints: Since the storage/conversion asset on-site is only running when there is excess electricity, its operating hours are low, putting pressure on the timeline for the return on investment.
Intelligent Grid Management/Dispatch
The third option to avoid or at least reduce curtailment is to manage the grid and its components in a smarter way. In many cases, grid operators have insufficient data on what is happening in their grid and shutting down excess electricity generation from wind and solar is the easiest but not most efficient of options. Alternatively, grid operators could ramp down fossil generation or decentralized generators that can catch up with lost production later on; they could ramp up power consumption in businesses and homes through national and/or local demand response programs or time-of-use tariffs; they could use existing decentralized storage options (e.g. from EVs or home storage batteries) on short notice.
Read more on curtailment in this informative article about curtailment in California.