‘Electrify everything’ has become a mantra in the fight against climate change. Switching a home’s heating, cooling, and other energy-intensive loads from fossil fuels to electricity could drastically reduce planet-warming emissions. But electrification has often run into a major, and expensive, hurdle: upgrading a home’s electric capacity. A home’s connection to the grid is rated by amperage, or amps, which caps the amount of current it can safely draw at once. The standard for houses built in the last few decades is generally 200 amps. Many older residences, however, have a lower limit because they were constructed when electricity powered little more than the lights, refrigerator, microwave, and perhaps the dryer. Research from Lawrence Berkeley National Laboratory found that roughly a third of homes in the United States have panel capacity of 100 amps or less. In the Northeast, that share rises to closer to half. As people install heat pumps, induction stoves, and EV chargers, they can run into a couple of potential issues. Their electric panel may simply run out of slots to install more circuit breakers, in which case the relatively easy fix of adding a subpanel often does the trick. But sometimes homeowners run into a bigger problem, where an electrician says all the new loads will push them past their home’s peak power limits. Upgrading an electrical service can start at a few thousand dollars and quickly skyrocket, particularly in rural areas or places where power lines run underground. ‘We’ve seen estimates of $10,000 to $20,000,’ said AJ Rossman, an electrical engineer with VEIC, a contractor that runs much of Efficiency Vermont’s state program. The exact scope of the problem is unclear. There is scant data on how many service upgrades are done each year, let alone those that may have been recommended and never made due to the cost. But the Lawrence Berkeley research suggests there may be thousands, if not millions, of homeowners who are told they need to upsize their service as they electrify. The good news is, there are workarounds — if you or your electrician know where to look. It’s a lesson my wife and I recently learned. When we moved into our Burlington, Vermont, home, natural gas powered the furnace, stove, and dryer. We knew we’d eventually want to electrify, so I had our service increased from 150 amps to 200. Because we needed the upgrade as part of other work, the bill wasn’t horrible. The change allowed us to install an EV charger, switch to heat pumps, get an induction stove, and plan for an electric dryer. We were happy to have a home largely free of fossil fuels. Then we decided to build an addition. Our plan for an extra 800 square feet would require two more small heat pumps along with lighting, outlets, and ditching our gas dryer. None of this was much of a concern until our electrician did the math. He determined that the laundry room swap alone would push our theoretical load to around 192 amps. Upgrading to 300 or 400 amp service would require trenching a new underground line and possibly even overhauling the transformer serving our block. It could cost us well over $10,000. Read Next They thought getting their home off fossil fuels would be straightforward. Chaos ensued. Tik Root I panicked and started digging for answers. I had heard about a growing array of products designed to help people in my situation. For example, a friend had installed a smart panel that monitors how much electricity each circuit is using to ensure demand does not exceed the home’s capacity. If things get close, the panel shuts off lower-priority breakers as needed, then turns them back on when it’s safe. This was appealing, but expensive. Converting my panel would have cost around $4,000 in materials alone. Even options that control a few circuits starts at about $2,000. With labor, the outlay seemed almost as staggering as a service upgrade. I came across a cheaper category of devices called load-sharing switches, or smart splitters. They allow two high-demand appliances to share the same circuit, with just one running at a time. That means only the heavier load counts in a home’s demand calculation. Each switch cost around $800, depending on the brand. The issue was that we would probably need at least two to bring our calculated load below 200 amps. That was certainly an improvement, but it still wasn’t cheap and it left little wiggle room for the future. There must be a better option, I thought. So, as a last-ditch effort, I called my utility provider, who I assumed may have other customers in a similar position. An advisor immediately asked me a question I had taken for granted: Is your electrician sure you need an upgrade? When my electrician had calculated how much power my house would need, it appears he used the National Electrical Code’s standard method. Simply put, this approach uses the rated loads of all the electrical items in a home to calculate its theoretical load. Using one of the many online calculators to replicate his work, I arrived at the same conclusion: I was already taking up about 187 amps and the addition would push me to around 227 — beyond the panel’s 220-amp limit. But Burlington Electric told me there was a lesser-known section of the code that could give me a very different answer. Commonly referred to as Section 220.87, even though it was recently moved to section 120.87, this method uses a year’s worth of utility data to identify a home’s actual peak demand instead of relying on hypothetical usage. Like 73 percent of residences around the country, my home has a smart meter, so it was relatively easy to request that information from my utility. A spreadsheet arrived the next day. The file was thousands of rows long, so I put it into TrueLoadapp.com, a tool electricians can use to evaluate a customer’s load using this alternative method. It parsed the data to find my peak, which came on January 20, when my home topped out at just under 62 amps. The code mandates a 25 percent buffer when calculating usage, which bumped me about 77 amps. Even then I was using less than 40 percent of my service and less than half what the standard method calculated. I then added my new loads the traditional way, and discovered there was more than enough capacity without upgrading my service. I had just saved thousands of dollars ‘My mission is to get anybody who is considering any sort of electrification to do this first,’ said Jake Marin, the founder of TrueLoad. ‘There are many, many, many situations where there is nothing wrong with your panel.’ Electricians work on a home’s electrical panel. Roughly a third of U.S. homes have 100-amp service or less, but research suggests only a small fraction may actually need an upgrade as they electrify. Jessica Rinaldi / Boston Globe via Getty Images Marin used to work at the VEIC, where he was involved in dozens of panel upgrades and started to wonder whether there was a better approach to the problem. That’s when he found 220.87 and built TrueLoad. ‘It tends to show that you have a lot more headroom than you actually thought,’ he said. ‘People are spending $10,000 or more that they don’t need to.’ This aligns with the Lawrence Berkely research, which found that only a small fraction of homes actually need an upgrade, especially when using 220.87. ‘Most electrical panels have headroom for additional load,’ said lead author Sean Murphy in a webinar earlier this year. Efficiency Vermont also looked into this issue, with similar results. ‘We’re finding it really depends on the electrician,’ said Rossman, who co-authored the white paper on the topic. It found that many electricians use rules of thumb in evaluating headroom, and few of those surveyed were aware of 220.87. Even homes with smaller services may have more capacity remaining than homeowners or electricians realize. ‘For a reasonable household, we are not seeing anything that comes close with the 200 amps,’ said Rossman, noting that even fully electric homes utilize a fraction of that. ‘And it’s rare where you need something with more than 100 amps.’ Whether a load calculation is accepted ultimately rests with local inspectors. Some don’t even require one. Those who do shouldn’t have a problem with 220.87 because it’s been around for decades, said Dean Austin, a senior electrical specialist at National Fire Protection Association. Master electrician Johnathan Quong, who owns New England Electric, has been turning to it for years, when the traditional calculation suggests a home lacks capacity. ‘We’ve been able to keep tons of people on 100 amp panels,’ said Quong, who added that he’s never had an inspector reject a 220.87 project. The bigger obstacle, he said, may be getting electricians to adopt it. At an industry conference this year where the topic came up, he said he sensed skepticism from colleagues accustomed to traditional calculations. ‘It didn’t sound like they knew about it, or didn’t feel like that was acceptable, and they still felt like it was their responsibility to make sure that it was 100 percent safe,’ he said. ‘In my mind, there shouldn’t be any resistance.’ One caveat is that homeowners must get usage data from their utility, and Marin said access varies widely. Some utilities print a home’s peak load on the monthly bill, and TrueLoad has a feature for helping users make requests, but customers can still end up having to dig for that data — and navigating the system isn’t easy even for experts. ‘I don’t even know how I would get that data from my own smartmeter,’ said Ric O’Connell, executive director of GridLab, a nonprofit focused on supporting a clean grid. A few days later he emailed to say that after ‘a long time’ and a battle with a ‘really poor’ user interface, he obtained his data from Pacific Gas and Electric Company in California. It showed that his home peaked at just 65 amps. For those who can’t access data, there are a few options. Another section of the code, 220.83 (recently changed to 120.83), allows some loads to be discounted based on the assumption that not everything in a home will be running simultaneously. In certain situations, that method may produce an even lower calculated demand than 220.87, said Jenny Low, director of panel optimization work and electrical reassessments for Build It Green, a nonprofit working to create equitable, healthy, and regenerative neighborhoods. At the very least, she said, it should be more forgiving than the standard method. If I had used that option, my addition would likely have squeaked in under 198 amps, which would not have left enough margin to make me comfortable. The 220.87 route was clearly the smarter move. The 2026 version of the code expands the options by allowing both demand data and load discounting, although adoption may vary depending upon which version of the code a jurisdiction currently uses. The bigger challenge is making sure electricians and homeowners know about it. For anyone who is short on capacity after using these approaches, load-management options like smart panels and switches are often the cheapest path to electrification. ‘There are,’ said Low, ‘lots of ways to avoid a panel upgrade.’ As for me, contractors broke ground on the addition last week. If all goes to plan, I will spend a grand total of zero dollars on an electrification project that could have cost me well over $10,000. This story was originally published by Grist with the headline This surprise cost could derail your heat pump or EV charger installation. Here’s how to avoid it. on Nov 12, 2026.