This is a question we’ve been getting a lot of recently. How many solar panels do I need to charge a Tesla? What about a different brand of car? Can solar panels even fully charge cars yet? Since the topic is gaining increasing attention, we’d like to shed some light on the finer details.
Most electric cars power themselves through a special electric vehicle adapter, called an EV adapter, installed into your home's electrical panel. How far a full charge will get you (and at what cost) depends on two key factors:
Your car’s mileage rating
The cost per kilowatt-hour from your utility
While “miles per gallon” is the typical way we think of gas-powered cars, “kilowatt-hours per 100 miles” is the standard for electric cars. It’s a bit different than ‘miles to the gallon,’ but essentially aims to reach a similar measurement.
Think of it like this:
On average, an electric car (as of this writing) may require anywhere between 27-32 kWh to travel 100 miles.
Your electric bill should be able to show you what your utility is charging per kWh, though the national average currently sits around 13.19 cents per kilowatt hour (kWh). Rates on Long Island average around 21 cents per kWh.
27 kWh x 21 cents = $5.67 per 100 miles.
Using the formula above, you can estimate your costs around an average year of driving. Say you average 12,000 miles per year. You can expect to spend somewhere in the neighborhood of $680 yearly (or $56.66 per month) on fuel costs.
How Green is Solar Energy?
Purchasing an electric vehicle (“EV” for short) is one of the most environmentally responsible decisions you can make, and helps society move toward a more sustainable model.
Experts agree: EVs create a lower carbon footprint than internal combustion vehicles over the course of their lifetime, eliminating tailpipe emissions altogether – and providing the opportunity to harness electricity produced from sources other than coal and natural gas.
Of course, there is a drawback: most EV cars are charged by the grid. And the grid relies on fossil fuels to generate 60% of our national energy production. This can upset some electric car enthusiasts who are looking to “go green,” only to find out fossil fuels are still part of their carbon footprint.
New York obtains some 30% of its electricity net generation from utility-scale renewable sources, so currently charging your electric car from the grid may indirectly cause consumers to be powering their car from a fossil fuel source (whether they know it or not).
But hope is not lost! That’s beginning to change.
The Solar Shift
The good news is that the rise of in-home solar production could soon lead to the electric car truly satisfying its green intent. Wind power, hydropower and other sources are also making their own contributions, though for most home consumers, accessible solar production could pave the way for a true alternative grid-powered vehicles.
PSEG & LIPA Electric Rates
Now that you understand the amount of energy required and the potential cost savings of electric vehicle solar charging, it’s time to take a finer look at how your electric bill works. This is a less commonly understood topic, and it’s an important one – people often try to predict what global events mean solar price changes, and if you’re not heavily involved in the industry, it can be difficult to discern fact from speculation.
For a full breakdown of what each of these terms mean and how to evaluate your electric bill, click here to download our PDF on the topic.
How do PSEG Rates Change?
Power supply charges float (vary) with current energy (primarily natural gas) prices and are recomputed every month based on what PSEGLI paid for the energy they delivered. New supplies are unlikely to come online due to:
bad investment dynamics (banks no longer funding development, global demand now unstable due to pandemic/conflicts, institutional investors divesting from fossil fuel)
environmental regulations to slow climate change (Paris accord)
Short-term demand is increasing – natural gas can now be liquefied (into LNG) and shipped from gas rich countries (including the US), to energy-poor countries around the world. It is unrealistic to expect that domestic natural gas prices will be much lower than global gas prices (and Mobil/Exxon etc.) are part of a global economy.
The graph below shows the PSEGLI supply charge trend over the last 10 years (based on analysis of GreenLogic client PSEGLI bills):
Knowing the governing forces behind these rate changes, you should have a better understanding of how these charges change across time.
Where Solar Fits
Once you have an estimate on your electric car’s refill costs, the conversation with your solar installer should be fairly quick and easy. You will be able to work together and build a home charging station with the right equipment, number of panels, and EV charger if needed.
While we may be generations away from a solar panel directly powering a car, offsetting your car’s energy needs with solar power pumped into your home is among the most environmentally conscious decisions that can be made at this point in time.
In addition, Federal tax incentives can allow for more savings — with our home installations now offering flexible $0 down financing options, working solar power into your home could pay dividends for you, your bank account and the environment all in one swoop.
Wondering how much solar you'll need for your electric vehicle? Fill out the form and our team will reach out as soon as possible.