As we deploy more renewable generation, the electrical distribution grid is quickly becoming the cleanest source of power in the state. A few years ago, most policy folks thought it would be a stretch to have 50 percent of the electric supply from renewables by 2025. In reality, we are already way ahead of that goal; in fact, there are times when 63 percent of the electricity on the grid is from clean, renewable sources.
But if we as a society want to take full advantage of the clean energy on the California grid, we will have to convert the majority of energy-consuming devices in our buildings to all-electric. Recent changes to building codes support this effort, requiring that new homes have electric services in place for all major appliances and solar panels on the roof. These are essential steps and will go a long way toward reducing our impact on the environment. To have a measurable effect on greenhouse gas emissions, though, we will also have to address existing buildings–a more significant challenge.
Clean energy enthusiasts like to focus on shiny objects, the latest in technology, the most visible solutions. The danger, though, is that we overlook the barriers created by things that are not as flashy. In this case, the problem is outdated electrical service panels (breaker boxes).
Modern homes likely have a 200 amp or larger service panel, as loads have increased over time. However, most homes over 30 years old have 100 amp or 125 amp service panels. One hundred amps was plenty of power when all you needed was a few lights and some basic kitchen appliances. As we convert the large energy-consuming devices in the house to all-electric, we will need to address service panel capacity.
Policymakers and rebate program designers have identified electrical service panels as a significant barrier to building electrification. The main reason is that electrification requires replacing service panels in most cases.
Who is Responsible for the Panel?
Our electric distribution grid used to be a one-way street. Typically, generation occurred at a remote location. High voltage transmission lines carried the power to local distribution networks and substations, where transformers stepped down the power and delivered it to our homes and businesses. It was essentially a one-way flow from the generation source to the end-user.
Residential solar generation has flipped that model on its head. Homeowners are now electricity producers too. Electricity now flows from utility generation sources to the end-user and–when homeowners’ photovoltaic systems generate more power than the homeowners are using–from the end-user back to the utility.
The concept of selling electricity back to your utility has changed everything. Well, almost everything.
One thing that hasn’t changed is the line where the utility’s responsibility for electrical infrastructure ends and the end user’s begins. When the utility supplies power to a building, it is responsible for delivering that power from the pole, or underground vault, to the electrical meter. All wires, circuit breakers, sub-panels, and other devices after the meter are the homeowner’s responsibility.
In a one-way flow distribution model, this works pretty well. But as soon as you start having energy flow to and from the end-user, the whole situation changes. If you have grid-tied PV, you are likely sending some power back to the grid when you are overproducing.
Many Reasons to Upgrade
Upgrading your service panel is a good idea in any case. There are multiple reasons to do it even if you’re not considering electrification. But if you do choose to go all-electric and your service panel is old, more than likely you will need to replace it.
Often, panels are replaced due to capacity. Older service panels may not have the amps required to supply the power required by new electric appliances. Each new electric device you add increases the need for capacity. Lack of capacity is especially true for large loads, such as heat pump space heaters, heat pump water heaters, and electric vehicles.
Another limitation of older service panels is physical space. As we add new circuits for electric devices, we need to add new breakers. Frequently, service panels have the capacity (amps) but no room to add more circuit breakers. There are some tricks, like installing “mini” breakers, which can fit two 110v breakers in the space usually occupied by a single circuit breaker. Mini-breakers can help free up space, but there are limits. 240V breakers, such as those required by heat pumps and EVs, are physically large, as they have to connect to both bus bars in the panel. You might be able to free up some space with mini-breakers, but often it is not enough.
Perhaps the most compelling reason to upgrade service panels is that the older ones are dangerous. There are two old brands of breaker panels that keep electricians in business, Federal Pacific and Zinsco. Do a quick Google search on electrical panel fires, and you will see what I mean. I am sure there are other brands with issues, but I have real-world experience with both of these brands.
In one case, we did an energy audit on a home. There was some funky stuff happening with electricity in the house, my business partner and I turned off breakers, one by one, to identify the problem and to label the breakers. Two days later, the homeowner had an electrical fire in her bedroom. The damage was minimal, thankfully, but there were lots of fingers pointed at us. It turns out the Zinsco breaker did not trip when it should have. The lamp cord got hot and started a fire. That’s scary.
The other example happened about a month ago in my own home. Our electric dryer stopped working. It was near the end of its useful life, and we were not surprised it failed. We braved the pandemic, put on our masks, and went to a retailer to buy a new washer and dryer. I installed the dryer, including a new pigtail (cord), to make sure it was all new.
However, it didn’t work correctly. I used a multimeter to check the voltage and got some very unusual readings. After some testing, I deduced there was likely an issue with the circuit breaker. I am pretty handy, and I have worked as an electrician’s assistant before, but I draw the line at working in breaker boxes.
I contacted an electrician to figure it out. Sure enough, the problem was in the Federal Pacific panel. The dryer breaker got hot and failed to trip. Instead, it melted and fused itself to the bus bar, putting it permanently in the “on” position. I feel fortunate that it did not result in a fire. I think it’s safe to say that both my wife and I are looking forward to replacing our panel.
Another advantage of modern service panels is that most have a master disconnect. A master breaker allows you to kill all of the power in the building with one switch, something to consider when you live in wildfire territory.
Replacing panels is not cheap. To update an average service panel is about $3,000 where I live. Replacing them also takes time, as you need to relocate all of the old circuits to the new panel before it is energized. It can also take weeks before the utility is available to come and switch the supply from the old panel to the new one. All of these factors contribute to making panel replacements a significant barrier for many people looking to convert their homes to all-electric.
Some rebate programs, such as the SMUD program we manage, have incentives for panel upgrades. For the most part, though, panel upgrades are not a utility’s favorite thing to do, as they are expensive, and the utility can’t get credit for the energy savings. In California, mandates require utilities to dedicate a certain percentage of their resources to energy efficiency. If something saves energy, it is more likely to get rebates than something that does not. The lack of energy savings from panel upgrades makes it hard for most programs to justify the expense.
If policymakers want to support electrification, they need to start by funding electrical service panel replacements. Having an old, sub-standard electrical panel is limiting my electrification efforts, and I am an energy geek. For the average consumer, the added cost of a panel upgrade is a deal-breaker. Heat pump water heaters, heat pump space heaters, induction cooktops, electric heat pump dryers, and EV chargers are great things. None of them matter if you haven’t addressed replacing the panel first.
I believe that panel upgrades should be considered the gateway to electrification. If we had state-level funding and an aggressive service panel replacement program, it could serve as the starting point for electrification. Imagine the sales pitch: “I understand you just had your panel upgraded. Now we should talk about how best to take advantage of super-efficient electric appliances.”
Service panels are a real and significant barrier to electrification. Their high cost and extended time to replacement is limiting electrification. Let’s start with an aggressive program statewide to get rid of these dangerous and outdated devices and use the opportunity to promote electrification. Sometimes the first step toward real change is not the shiny object. Electrical service panels are not sexy, and they are expensive. But we need to address this issue first, and then we can let the sales guys come in and sell all of the shiny objects they want to, once the circuits and power are there to support them.
What are your thoughts? Leave us a comment below.