Free Electric Car Charging for Life with Grid-Tied PV Solar

Electric car charging linked to solar with professional installation adds cost effectiveness to your system. From a sustainability perspective alone, home EV (Electric Vehicle) charging and PV (Photovoltaic) solar panels are a natural marriage of complementary technologies. During operation, neither systems consume fossil fuels or other non-renewable sources, nor produce ozone depleting pollution or global warming emissions. Installing a properly sized solar array could effectively supply all electricity necessary to charge and power an electric vehicle. Therefore, a solar system could eliminate a family’s transportation fuel cost indefinitely. 

Sizing PV Solar for Electric Car Charging

Electric vehicle battery capacities typically range from 20 kWh up to 100 kWh for longer range vehicles. An average battery size of 50kWh generally provides 150 miles of range. According to the U.S. Census Bureau, the average commute in Kansas City is 15-25 miles or 30 to 50 miles round trip per day. Given, an average battery capacity and daily commute, and 6 days of driving per week, the electrical vehicle would require a charge once every three days or 33% each day. The total EV energy use would be nearly 400 kWh per month. According to the EIA (U.S. Energy Information Administration), the typical U.S. residential home consumes an average of 887 kWh per month. Therefore, adding an electric car charger may add nearly 50% more electricity use per month. Pairing a properly sized solar array with a level two EV charger could effectively eliminate a home’s transportation fuel cost without any additional home energy. Alternatively, a solar system could be sized and designed to offset both transportation costs and total home electric utility bill. Various sizing methods exist to achieve net-zero operating energy. The most aggressive technique installs a private power plant based on the home’s highest kWh month, which usually occurs in the hottest or coldest month of the year, depending on the local and regional climate. A more conservative method averages energy consumption over a year, sizing the system to produce at that level, therefore achieving annualized net-zero through net metering. 

Advancements Make Solar Cost Effective for EV Charging Stations

As PV solar technology continues to mature, higher levels of equipment efficiency are achieved at ever lower costs, encouraging installation of more residential solar systems. Research by NREL (National Renewable Energy Laboratory) found steady improvements both in total module power production and panel efficiency. As an example, ten years ago 160-watt residential panels were considered high performing, today panels are routinely achieving 350 to 400-watts, more than double the energy harvest of a decade ago at the same price. Additionally, the introduction of MLPE (Module-Level Power Electronics) such as micro-inverters and DC (Direct Current) power optimizers allow for enhanced designs with more energy production. Furthermore, NREL found over a five-year period MLPE costs have fallen nearly 30% further reducing solar installation costs while producing more electricity. 

Economics of PV Solar When Paired with an Electric Car Charging Station

According to the EIA the annual price increase for electricity in the U.S. has risen 1.25% on average per year for the last six years. Meaning the rate residential homeowners pay per kWh continues to go up. Increased numbers of electricity consuming appliances, computers, phones and other electronics have increased energy use in homes. Albeit some energy use has been, and can be, offset through energy conservation measures such as weatherization, selection of high-efficient heating and cooling equipment, appliances and hot water units. The campaign to eliminate gas (natural, propane, and gasoline) usage for home heating, cooking, and vehicles will no doubt hasten electrification in the United States. As electrification takes hold, significant increases in electricity demand and grid loads will follow. The future landscape for cheap electricity in the United States does not look good. NREL is conducting a multi-year study assessing the impact of electrification on U.S. utility infrastructure. Given societal trends and political aversion to traditional power plant fuel sources, namely coal and natural gas, coupled with U.S. regulatory constraints for construction of new power plants, we are unlikely to see large increases in consistent base power supply. Therefore, expected increases in electricity demand will accelerate electric rate price inflation. A PV solar system effectively fixes the price of electricity for the homeowner. The cost per kWh is determined on the initial capital investment of the solar array divided by the systems energy production and longevity of the infrastructure, typically 30+ years. According to Sunmetrix, an online resource for homeowners, residential PV solar power plants have already achieved price parity with residential retail electricity rates in much of the United States. Price parity is when the levelized cost to install PV solar is equal to the retail rate for electricity from a conventional coal or natural gas power plant on a per kWh basis. Sunmetrix grid parity map finds both Missouri and Kansas have reached and surpassed grid parity, making installation of a PV solar plant more economical than purchasing electricity from an electric company. Additionally, purchasing a solar array today locks in the savings against future higher electricity rates from the utility. The levelized cost savings of solar is $0.0454 per kWh and savings in the state of Kansas are even better at $0.0653. 

Incentives for PV Solar

Currently, the U.S. federal government supports and encourages installation of residential PV solar systems by offering a 26% tax credit (not deduction) for the total installation cost of PV Solar arrays. In 2020, the federal government extended this incentive through 31 December 2023. Without further legislative action, this tax credit will decrease each year eventually expiring. Beginning 1 January 2023, the tax credit decreases down to 22% ultimately expiring 31 December 2023. Below are some additional facts about the energy efficiency federal tax credit:

• Credit may be combined with other available energy efficiency incentives
• No maximum limit to this tax credit
• Can be used in more than one year 
• May be used to offset alternative minimum tax (AMT)

Home Performance Group Charging Station Installation in Kansas City

Interested in installing an EV charging station with PV solar, consider hiring a full-service electrical professional with specialized knowledge to properly design, size and install your charging station and independent solar power plant. A small upfront investment in careful design can save both the headache of inconvenience and thousands of dollars future rework.

At Home Performance Group, we continue to invest in technical training so we can correctly design, specify, size, and install electrical systems, solar systems, and electric care charging stations. We have performed numerous projects for our clients.

If you are interested in a no-cost in-home consultation, schedule with a Solutions Advisor today. 

Article by Larry L. Motley Jr., 13 Sep 2021

Larry is a graduate of both Wentworth Military Academy and Missouri Western State University earning a double bachelor’s degree in Economics and Finance. Additionally, he maintains six professional tradesman licenses in two states and advanced credentialing in green technology, project and program management, and process improvement. Larry is a three-time combat veteran having served in Operation Iraqi Freedom, Operation New Dawn, and Operation Inherent Resolve. He continues to serve through a value-based building science company focused on providing clients the best design, highest quality installation, and most honest repair services in the community.