Renewable power sources make up an ever-larger share of our energy system. Unfortunately, however, we cannot always rely on the sun to shine and the wind to blow. It will thus be difficult to balance energy supply and demand. Innovative energy storage technologies may provide a solution, but we may also have to ask consumers and businesses to adjust their energy use to match erratic power supply.
- In OECD countries, intermittent renewable energy sources (i.e. wind and solar) already accounted for 8,4% of all electricity produced in 2016. In Denmark (52.4%), Spain (23.2%), Germany (20.2%) and specific parts of the US (e.g. California and Hawaii) this share is even bigger.
- There’s a growing market for energy storage solutions at various scales. Grid-scale storage systems are installed worldwide: a 50MWh battery system (i.e. the equivalent of 500 Tesla Model S’) is planned for installation in Germany. Projects in California have already resulted in 80-120 MWh storage batteries. Thermal solar power plants are also able to store heat for up to ten hours after sundown, but these are only suitable for desert-like environments.
- Small scale storage systems for businesses and households (i.e. ‘behind the meter’) are on the rise as well and, for instance, the market for distributed solar generation and storage systems alone is estimated to grow towards USD50bn by 2026.
- A major Australian housing developer, Metricon, offers solar panels and storage systems as an optional extra in newly-built homes. With the system, homes could be taken off the power grid.
To balance supply and demand in future energy systems, technological solutions will be required. For local or regional systems, grid-scale storage facilities will be deployed to store renewable energy for later use. (Inter-)nationally, long-distance cables will be required to transport electricity wherever it is needed most. All of these technological fixes are promising, but they are also expensive (e.g. massive li-ion batteries) and necessarily limited in terms of capacity.
We may have to ask consumers and businesses to adjust their energy use to match erratic supply
Complementary to these, we may need to adjust our energy needs throughout the day, but this is easier said than done. Energy consumption is merely a derivative of everyday practices such as cooking, housekeeping, communicating or watching television. These practices are deeply intertwined with the technologies we come to use and the routines we’ve built around them (e.g. watching the eight o’clock news). Adjusting these routines to match energy supply could be possible through financial incentives, but for a couple of cents were are unlikely to postpone cooking or wait half an hour before we turn on our TV.
There are nevertheless quite some devices in our homes (and offices) that can regulate their own power consumption without impacting our everyday routines. Washing machines, dish washers, refrigerators or EV chargers could all communicate with the grid and decide autonomously when to start drawing power. Other devices could probably do the same when they are equipped with relatively small batteries that allow them to operate off-the-grid for some time. As such, consumers can gradually build a smart and grid-friendly home without having to invest thousands of dollars at once in a bulky storage battery in their basement.