05 February 2023 |

More than a charger


EV charging is a hot investment area. While investments in electric auto manufacturers have taken it on the chin a bit of late (Rivian is down some 70%+ since IPO), hundreds of millions of dollars pour into EV charging companies on what seems like a weekly basis. For example, ABB E-mobility raised ~$355M in pre-IPO funding this week to continue expanding its EV charging footprint beyond the 85 markets in which it already operates. 

While not capital-‘light’, charging infrastructure can be a less capitally intense entry point for investors than making cars themselves. EV charging has become the du jour way to get exposure to the growing EV pie. It’s not too hard to see why there’s a solid amount of salivation for said pie – it’s going to be a big one. As per our Thursday email, by 2030, ~2% of all U.S. power gen could be devoted to charging EVs:

Of course, EV charging is a vast category in itself. The world will need chargers across countless potential charge points to accommodate more EVs, whether on highways, cities, residential garages, or elsewhere. And chargers will vary across car makes, models, sizes, etc. 

And even within the category of, say, consumer EV chargers designed for the home, not all EV chargers are built the same. One key differentiator beyond charging times and car compatibility? Few EVs and / or chargers offer bidirectional charging. You use chargers to charge your EV. But if you want to reverse the flow and run your house on your EVs battery during a blackout, you’re ‘SOL’ with most cars and chargers. 


The reason most EVs and chargers don’t offer bidirectional charging yet isn’t mere oversight. Power from the grid always comes in the form of alternating current. EV batteries require direct current. EVs have built-in converters that convert alternating current to direct current. Some chargers can also handle this conversion themselves — these are called ‘DC’ chargers. One benefit of DC charging is speed.

If you want to take power back out of an EV battery and use it on the grid, you  need to translate from DC (from the EV battery) back to AC (for the grid). This requires an inverter, a second device, in addition to the converter. If all these conversions and inversions feel like a Highway to Hell (*sorry*), don’t worry. It’s a real hurdle that most manufacturers have punted on so far. 

That’s changing slowly though. This week, Enteligent raised $7M from investors for its portfolio of solar and EV charging products. One of its products is a bi-directional EV charger (it can handle conversions from DC back to AC) that can also use electricity from solar panels directly.

Solar power generate DC, which is converted to AC before it can be used in a house or sent back to the grid. That means it also has to be turned back into DC to charge an EV battery. Power is lost during these conversions, meaning Enteligent’s direct solar-to-EV charger also offers energy efficiency gains.

The net-net

Unlocking vehicle-to-grid (‘V2G’) and vehicle-to-home capabilities will help with many things. It will turn EVs into backup batteries for homes during blackouts. It will grant residential rooftop solar systems valuable battery storage capacity, making them more productive assets overall. And, managed effectively and at scale, EVs will become a reservoir of energy storage to decarbonize the grid.

Unlocking V2G is also necessary to enable more rooftop solar adoption. In 2015, Hawaii had to restrict new grid connections for residential solar systems because the grid couldn’t handle all the new, variable generation from solar. Adding storage to solar energy systems is critical for all the reasons we named above and for basic grid balancing.

Finally, making V2G happen should also not rest solely on auto manufacturers’ shoulders. While a few cars, like the Ford F-150 Lightning, offer bidirectional charging, it always still requires additional chargers and power systems, at additional cost. Best not to leave everything up to auto OEMs, they have a hard enough time keeping their heads above water.