Increasingly — at least once each week — we are contacted by solar homeowners who recently purchased, or are contemplating buying, an electric vehicle (eV). To wit, they are interested in adding panels to their current solar system to cover fueling (charging!) their new eV.
The good news: Solar-charged electric vehicles are the least expensive form of four-wheel transportation, let alone the virtue of aborting fossil fuels. For RepowerYolo homeowners, the average cost to generate solar electricity on their rooftop is 8 cents per kilowatt hour (kWh). For every kWh of charge, eV owners garner ~4 miles of range. Hence, if you have an electric car that’s powered by sunshine, your cost to drive is ~2 cents per mile.
The challenge: While it’s technically (almost lego-esque) easy to add solar panels to a system, the process is, unfortunately, somewhat pricey. There are two scenarios:
1. Your current inverter has sufficient capacity to accommodate additional panels. If this is the case, then the challenge is locating and purchasing comparable (wattage) solar panels. Depending on the vintage of your current system, this could be simple, or it may be that you need to purchase used/refurbished panels.
2. Your current inverter cannot accommodate additional solar panels. Thereby — this is what I did when I added nine panels on my roof to charge my Leaf — you need to either add a second inverter or proceed with micro-inverters. Again, securing compatible panels is the next step.
In both scenarios, we are required to perform full design-engineering-permitting for your additional solar capacity. Though this is not complicated, it adds to the cost; it’s not simply lego-esque, snap-a-few-panels-in-and-go.
An additional caveat: Homeowners can only claim the 30% Federal tax credit once every five years. So, if you went solar in the past five years, you may want to wait until you re-qualify for the credit.
Net-net, we’re happy to help. There’s no cost to receive an assessment of your current system, analysis of your historical net-energy use, modeling of your future electricity demand (for your eV), and an analysis + recommendations for your additional solar capacity. Feel free to contact us or swing my our workspace.