By Randy Bryan
Electric utilities have resisted renewable power (solar) growth in various ways over the years. Many utilities have seen solar installations as a threat to their legacy business model (monopoly-regulated-safe central supply to secure growing customer base). Solar has been a distributed ad hoc supply source, bleeding demand away from the central generating stations, while creating riskier supply. Utilities have feared this as the early stage of a death spiral where their constant expense base must be paid for by ever less revenue and fewer customers. The business response is to contain the solar problem to a token percentage of business (restricting net metering and incentives) and/or to raise rates on the fewer customers remaining. However, raising rates would cause even more customers to leave and/or augment their power supply causing a death spiral.
The dropping cost of solar and wind energy and batteries make renewables equal or lower cost than utility power, even without incentives. Batteries allow solar power to be demand-driven (base load) rather than supply-driven (when the sun shines or wind blows), which may enable customers to leave the utility completely to go “off-grid.”
This business view has been widely reported and discussed within the industry. I believe this “death spiral” fear is completely wrong and is, in my view, a self-conjured danger. In fact, another recent technology trend may make solar a savior of the utilities, rather than their demise. That new trend is electric transportation (electric cars, trucks, and buses).
To build my case, I offer some background information:
The typical home solar installation is about 5kW, yielding about 15kWh of energy in a day. The average house load is about 20-25 kWh per day. So, on average, where houses/businesses can have solar, solar energy supply potential is less than existing building demand. And don’t forget, many sites cannot deploy solar due to roof availability such as orientation, shading, or neighborhood restrictions.
Enter the electric vehicle, ready or not. Electric vehicles are only about 1% of the vehicle market now. But, their market growth is expected to mushroom (about 25-30%/year), equaling 15% by 2025 and 25-30% by 2030, eventually replacing combustion vehicles all together. This automotive industry prediction is due to the falling cost and growing capabilities of batteries, the lower cost to manufacture electric cars versus combustion cars, and the lower operating costs of electric cars (less maintenance and lower cost of electricity per mile). Added to this cost case is the growing list of countries, states, cities, and companies mandating all electric vehicles fleets by some future date, to the exclusion of combustion vehicles.
The typical electric car will need sufficient battery capacity to travel 300-400 miles per charge (100-150 kWh). But, most people average about 50 miles per day (15-20kWh) in their primary car and maybe half that for a second car. To put it another way, the primary (electric) car will add about a new house worth of load and the second (electric) car about a half house. Much of this charging will occur at night, at home. For longer range driving needs, or electric cars without a convenient nighttime charger, other day-time charging supply will be needed, likely in the form of gas-station/parking-lot-like charge sites, which will serve about 20% of the overall transportation charging needs.
To summarize my case, electric vehicles will cause a significant increase in overall electric demand (up to 50% more, if all vehicles are electric). Most (80%) of the demand will occur at night, with rate incentives, and generate additional revenue from existing grid assets, perhaps stabilizing grid rates. Where vehicle charging is needed, external power supply will most certainly be needed, assuring the continuing and growing need for utilities’ power.
The day-time charging needs of electric vehicles could significantly boost the prime-time power or energy demand and overwhelm the grid as currently built. A potential solution is to ramp up solar power installations (with battery for some buffering) as a clean and local source of energy that closely matches the added day-time charging loads of electric vehicles. Throttling of vehicle to grid connections is a second order issue and a separate discussion.
I suggest that electric utilities will be saved, not ruined, by electric vehicles and solar power. And they go together. As such, utilities should become active advocates for both electric vehicle sales and solar installations, as the best, cleanest, and safest course toward a profitable and reliable grid future.
Randy Bryan has been an advocate for electric cars for eight-plus years. His company, ConVerdant Vehicles, has converted vehicles to plug-in hybrids, including his own Prius in 2008, and developed and sold inverters that turn a Prius into an emergency generator. He is one of the co-founders of Drive Electric NH.