PG&E, GM, Ford to test EVs as whole-home battery backup

In early March 2022, GM announced a partnership with PG&E to begin a pilot program to test bidirectional EV charging. This means that they will test whether or not car batteries can be used as a backup power source for homes or the grid in the event of an outage. Ford Motors is also part of the partnership, but they didn't have such a flashy press release.

What does this partnership mean for EV owners? For now, not much. But if the pilot goes well, there is a lot of potential for homes to use EVs as a backup source of power. It might seem far-fetched, but it's actually more plausible than you may think.

How will EVs work with the grid?

Bidirectional charging can be confusing, but we'll start with an easier concept - solar batteries. These days, many people who have solar panels choose to add battery storage to their home as a backup power option. Solar batteries store electricity that can be used during times when solar panels are not producing electricity, like at night.

Car batteries can be used to store energy in a similar way to solar battery packs. However, car batteries tend to have a larger storage capacity, ranging from 28 kWh - 200 kWh, compared to less than 20 kWh for solar batteries.

This is a huge source of stored energy that could be used as a backup source during power outages. PG&E, the main power supplier for the state of California, is looking into this as a potential solution to their aging infrastructure problems. PG&E had to shut off power to help avoid forest fires after their aging infrastructure was found to cause the deadly 2018 Camp Fire.

The problem is, as power outages become more common and the grid becomes less reliable, options like EV backup will be a key source of backup power for homeowners. If GM, Ford, and PG&E can get this right, they will be unlocking a new source of power for the entire country.

How will this pilot program work?

Bidirectional charging is the ability to use the energy from an electric vehicle's battery to power your home. This is possible, but has not been done on a large scale yet.

The goal is for houses to act as mini power grids. This would allow homeowners to generate their own power and also send extra energy back to the grid.

This is a way for homeowners to become energy independent. It also helps utility companies if something happens and people can't get energy from the grid. Normally, when companies see people wanting to use renewable energy options, like solar panels, they make those options less financially beneficial so that fewer people will want to use them.

There have been partnerships formed between EV manufacturers and solar companies to install chargers. An example of this is the partnership between Ford and SunRun. Recently, Ford and SunRun announced that SunRun will be the go-to solar panel and charger installer partner for people who buy Ford EVs. However, this is the first time a utility company has partnered with a car manufacturer.

Traditionally, utilities have been hesitant to work with anything related to renewable energy and electric vehicles. But PG&E is recognizing the need and benefit of creating this partnership in order to build the grid of the future. This will help us create a cleaner, more sustainable future.

When will the pilot begin?

This pilot project will start in Summer 2022. It will give homeowners the ability to charge their electric vehicles from their homes. The project will use software-defined communications to allow power to flow back and forth between the cars and the houses.

The press release is a bit vague on the details of how it will all happen, but if this pilot goes well, it has the potential to change the way we get electricity. Before PG&E, GM, and Ford install vehicle-to-home interconnection, there will be lab testing to determine safety and practicality. That is what the pilot is doing now (late March 2022).

Why is bidirectional charging important for a renewable electricity grid?

Renewable energy can be tricky. For example, solar panels cannot work at night and wind turbines cannot produce electricity if there is no wind. However, during the times that they are producing energy, it’s possible for it to go unused - resulting in 'excess energy'. To solve this problem, we have solar batteries.

Solar batteries are designed to absorb excess electricity and store it for homeowners to use during the times when their solar panels aren’t actively producing electricity. A car can also do this, but because the battery within a car is bigger than traditional solar storage batteries, EVs have the potential to play a much bigger role in storing electricity for emergency use.

There are approximately 16 million people in California who rely on utility PG&E for electricity. With more stress on the grid than ever, PG&E needs to find new ways to ensure homeowners will have the power they need, when they need it. Piloting the potential for EVs to be a source of backup power is a step in the right direction. This could mean that people with electric cars could charge their cars during times of emergency, and then use that power to help keep their homes running.

At the moment, you cannot just purchase a bidirectional charger yourself when buying a regular EV charger. The concept is still new, but this pilot can be the beginning of a brand new way for EV owners to help keep the grid running for everyone. And the fact that major companies are investing in testing this technology is a hopeful sign.

What needs to change for this to work with current EVs?

Bidirectional chargers have been in the works for a while. If they are set up correctly, they could help make the electric grid more renewable. The chargers have taken a while to become commercially available because there are a lot of things that need to be done in order to make them work.

You see, electric vehicle batteries store direct current electricity. This type of electricity is not used in homes, so it needs to be converted to alternating current. This is done with an inverter, which is a standard piece of equipment in a solar system setup. It is not impossible to do this, but it is not as simple as using the same wall charger that currently charges your car. The chargers currently on the market cannot send power back into your house for use.

Accepting energy that homeowners send back to the grid on a large scale is something that contemporary grids were not built to do. When thousands of cars do it, the grid will need to be upgraded.

What else should homeowners in California know?

California recently announced that by 2035 all light-duty autonomous vehicles must be emissions-free. They are already the top EV state in the country, with 320,000 EVs in San Francisco alone. These two factors make California a great place to test autonomous vehicles because there are plenty of EV customers who can try the product and it is also necessary to have bidirectional charging.

At this time, California homeowners cannot sign up to test the system within their home. However, homeowners can keep their eyes peeled for the option in late 2022 when it will be available.

You can also work with your car dealer to stay up to date on when you can get a bidirectional charger for your home. Keep in mind, you will need a GM or Ford EV, so now is the time to order one if you have not already.

The pilot has no defined ending yet, but if it is successful, we can safely assume that more EV manufacturers are going to work with utilities around the country to implement bidirectional chargers. This will eventually result in a cleaner and more sustainable grid in the future.

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