Could a new EV charger break the local grid? Probably!

Christopher Johnson
6 min readApr 15, 2024

In recent years, there has been a remarkable surge in consumer interest towards electric vehicles, with at least one in three adults considering an electric vehicle for their next vehicle purchase.

California stands as a prime example of the surge in EV adoption. With one in every four new vehicles hitting the roads being electric, California surpassed the state EV targets by at least two years.

But where will all these electric vehicles charge? And what will be the impact on the grid of switching from gas stations to the electrical grid to propel our vehicles? While home charging is not necessary for an EV, and not possible for one in three occupied homes, it certainly is convenient. But getting an EV charger may be more complicated than you expect, due to the cumulative impact of charging on the grid infrastructure.

For most of us, the flip of a switch is an everyday action we take for granted. But behind this simplicity lies an intricate web of infrastructure that is currently under strain.

The hockey-stick like growth of EVs is a pattern that most grid planning processes are ill-prepared for. This was highlighted in an extensive analysis of impacts of EV adoption on the California grid completed by the grid data analytics company, Kevala, last year.

This Electrification Impact Study found that massive amounts of equipment will need to be upgraded in the next 11 years! This includes nearly 500,000 service transformers (the metal cans mounted on poles in every neighborhood) as well as nearly 35% of feeders and 40% of transformer banks — an overall impact that could cost $50 billion dollars and cause massive logistical challenges.

Summary graphic from the Kevala’s report for the California PUC: Electrification Impacts Study Part 1

A Personal Story About The Domino Effect of Electrification

I end up talking about electrification a lot in hopes of supporting more of it. This led me to discover the situation of friends, residents of San Francisco’s Noe Valley neighborhood, who wanted to do a seemingly simple thing: installing an EV charger at their home. However, this modest upgrade initiated a series of events (and delays) that highlight the challenges facing our grid today.

The EV charger installation required an upgrade to the 100 Amp electrical panel in their house. While technically you can achieve electrification with a 100 Amp panel, often 200 Amps is needed as you decarbonize appliances. In this case, increasing the service to the house meant changing the wires that service the house to allow more electricity to flow.

This single residential service upgrade, however, triggered a more extensive upgrade: to the service transformer that is the last step in adjusting the power for many neighboring houses along 29th Street. What was initially a personal endeavor soon transformed into a wider project. And after more than a 9-month wait, the transformer upgrade finally happened onApril 5, 2024.

The old (25 kva) service transformer comes down (left) and the new 50 kva one gets wired into place.

The Strain of Electric Vehicle Adoption on Aging Infrastructure

As we stand on the cusp of an electric vehicle (EV) revolution, the demands on our energy infrastructure are rapidly evolving. After two decades of flat load growth, where utilities have not had to worry about growing the supply of electricity, significant load growth is now occurring across most markets and forecast to continue for years to come.

Not only does this mean securing more energy for customers, it means that the equipment all along the distribution grid will require investment to be able to handle the growing volumes of electricity we need for all aspects of our life.

As more and more Californians make the switch to electric, the strain on our already aging infrastructure will only intensify. The story from 29th St. is a stark reminder that in many places, the parts of the grid are already close to their limits and small changes will require upgrades. Are utilities going to be able to keep up with the demand for more EVs and electrification?

As we continue down the path towards a cleaner, greener future powered by renewable energy, strategic planning and investment in our grid infrastructure will be crucial.

If we just try to meet this demand by upgrading infrastructure, the costs will be so high that rates will become overly burdensome (check out the recent Rewiring America report on this). We have to get smarter about planning for the upgrades, integrating technologies to dynamically manage load, and incentivizing electricity customers to be good grid citizens.

During the pandemic, we started to hear about utility supply chain challenges for grid infrastructure. Large transformers used on higher voltage portions of the grid have been a headache for years.

But just in the last year, the lead time and prices on a distribution transformers has skyrocketed. According to Joy Ditto, president and CEO of the American Public Power Association, the time to procure a new distribution transformer has shot up from three months in 2020 to more than a year, with prices rising 200–300%.

However, in the case of this upgrade, the 9 month delay was not from a supply chain issue — this equipment was already in stock in San Francisco. The delays were instead due to the internal processes of the utility company and the local permitting authorities. And this project, according to the PG&E crew who carried out the work, was an easy one.

In some cases, a new transformer requires an upgrade to the pole (more delays) and if there is a tree next to the pole, that could add another six months to the process to deal with pruning and/or removal. This administrative red tape often leads to frustrating delays for homeowners and communities alike.

The members of the San Francisco PG&E crew that upgraded the service transformer.

This story serves as a microcosm of the challenges facing our grid as we move towards widespread electrification. And the delays are only likely to get worse as the impacts are increasingly felt.

California is the tip of the spear in this case, accounting for about half of EV sales in the US, but a similar pattern is coming for communities across the country. And while an electric vehicle is a popular choice, it is not the only electrification trend driving the rising demands on the grid — HVAC and water heaters are being replaced by electric heat pumps, induction stoves are replacing gas stoves, etc.

In order to avoid the headache and delays that may be caused from electrification, my advice is to plan ahead…like a year ahead! An easy first step is to get familiar with the main electrical panel (that gray box with breakers in it, usually close to the utility meter) and finding out how many Amps it is rated for. If it is less than 200 Amps, it will require a proactive and creative approach in order to avoid the timely, costly upgrades highlighted in the story above. But it is possible! Have a look at this great article from Canary Media on electrifying with a 100 Amp panel for further details on how to be successful.



Christopher Johnson

Christopher is a force multiplier called to accelerate the deployment and adoption of climate tech solutions at massive scale, and this blog shares the journey.