The concept of electric cars powering homes, stabilizing grids, and playing a pivotal role in integrating an ever-growing share of renewables into our power system is not new, but progress in making it a reality has been slow.
Intermittent wind and solar power in the European electricity mix are at 22.5% today and are expected to rise to 45% in 2030. More renewables require more flexibility, and EVs can provide that (almost) without any additional investment. A typical EV battery offers 3-4 times the energy capacity of a conventional home storage system, and while the latter comes with a huge price tag, the battery in the car won’t cause any additional cost. On the contrary, bidirectional charging could save EV drivers several hundred dollars per year.
If just 20%[1] of the EV fleet were connected to a bidirectional charging plug, this could meet nearly 90% of Europe’s short-term flexibility needs in 2030. This would save Europeans billions of dollars in home batteries, unnecessary grid upgrades, and subsidies for peak gas power plants that only generate electricity during rush hours.
If all of this is so obvious, why is bidirectional charging still a relatively small niche? A main reason is that most car manufacturers still see bidirectional charging as a gimmick, not a priority. Bidirectional charging infrastructure also lags behind because without enough bidirectional-capable vehicles, who would invest in a more expensive bidirectional wallbox? The few bidirectional chargers available are expensive and may not be compatible with all cars, further discouraging consumers.
To turn the “batteries on wheels” dream into reality, at T&E, we believe that policymakers need to urgently clear all barriers that hinder people from using their cars as home energy storage. Allowing individuals to sell excess power from their vehicle batteries back to the grid, coupled with smart grid tariffs, or simply giving them the possibility to use the stored energy to power their home can boost the bidirectional charging business case.
Governments need to set the right regulatory frameworks. This includes harmonized specifications for bidirectional chargers – making sure they work with any EV. More importantly, regulation needs to ensure that all newly sold EVs are bidirectional vehicles that can be used as energy storage ideally for their whole lifetime.
The case to transform EVs into virtual power plants is clear: EV drivers can massively profit from it, our energy system is going to need it, but car manufacturers aren’t delivering. We need to act soon or lock out millions of EVs from this technology and its benefits. Governments and regulators need to act soon, so everyone can fully utilize their ‘battery on wheels.’
[1] Based on T&E’s preliminary internal calculations
