Here's how school buses could support the power grid
David Wagman | September 02, 2019
The first phase of the electric school bus deployment is estimated to cost $13.5 million and aims to have 50 buses on the road by the end of 2020. Source: Dominion Energy
Dominion Energy Virginia said it plans to help electrify school bus fleets across the state.
The utility is opening a request for proposal (RFP) process for school bus manufacturers to supply vehicles. School districts can raise their hand to express interest in taking part in the program. Bus deliveries could begin as soon as 2020.
Plans call for the electric school buses to serve as a grid resource by creating additional energy storage to support Dominion's integration of distributed renewables such as solar and wind. The vehicle-to-grid technology uses the bus batteries to store and inject energy onto the grid during periods of high demand when the buses are not needed for transport.
As part of the state's 2018 Grid Security and Transformation Act, Dominion is working to secure around 3,000 megawatts of new solar and wind energy capacity by 2022. Energy storage made possible by technologies such as electric buses can help smooth the intermittent nature of that renewable energy resource.
The first phase of the electric school bus deployment is estimated to cost $13.5 million and aims to have 50 buses fully operational within Dominion Energy's Virginia service territory by the end of 2020. Phase two of the project, with state approval, would expand the program to bring 1,000 electric school buses online by 2025.
Later phases set the goal to have 50% of all diesel bus replacements be electric by 2025 and 100% by 2030.
Electric school buses already are being deployed in other parts of the country. In California, for example, bus manufacturer Blue Bird said that it has orders for nearly 100 electric school buses that are powered by Cummins drivetrains. The buses are capable of up to 120 miles of range and can be recharged in roughly eight hours using a standard SAE J1772 Level 2 charger.
In Virginia, Dominion said that replacing a diesel bus with an electric bus is the equivalent of taking 5.2 cars off the road.
Under the program, Dominion Energy will offset the additional costs of an electric school bus, including charging infrastructure, above the standard cost for a diesel bus. The utility said that operational and maintenance costs are also lower with electric school buses, providing a potential reduction of as much as 60% per year for school districts.
Has anybody made a study to check the reduction in battery life associated with increased charge/ discharge cycles? Great idea to use the spare capacity to even out the variability of solar but if this excessively reduces the lifetime the overall benefits could be negative with increased mining and production greenhouse production.
The solar road seemed a good idea to somebody, ( not me), somehow the obvious decrease in generation caused by dirt, leaves, motor emissions, breakages was overlooked
Interesting idea as I'm from Virginia. But..a friend sent me this e-mail a short while ago. I haven't done the research myself , I'm just reposting so take it with whatever grain of salt you choose.
The ACTUAL COST of driving an electric car This is for Engineers out there, surely there should be a rebuttal to this article. Say it isn't true! As an engineer (Writer) I love the electric vehicle technology. However, I have been troubled for a longtime by the fact that the electrical energy to keep the batteries charged must come from the grid and that means more power generation and a huge increase in the distribution infrastructure. Whether generated from coal, gas, oil, wind or sun, installed generation capacity is limited. A friend sent me the following that says it very well. You should all look at this short article. INTERESTING - ONE OTHER QUESTION. IF ELECTRIC CARS DO NOT USE GASOLINE, THEY WILL NOT PARTICIPATE IN PAYING A GASOLINE TAX ON EVERY GALLON THAT IS SOLD FOR AUTOMOBILES, WHICH WAS ENACTED SOME YEARS AGO TO HELP TO MAINTAIN OUR ROADS AND BRIDGES. THEY WILL USE THE ROADS BUT WILL NOT PAY FOR THEIR MAINTENANCE! In case you were thinking of buying hybrid or an electric car: Ever since the advent of electric cars, the REAL cost per mile of those things has never been discussed. All you ever heard was the mpg in terms of gasoline, with nary a mention of the cost of electricity to run it . This is the first article I've ever seen and tells the story pretty much as I expected it to tell it. Electricity must be one of the least efficient ways to power things yet they're being shoved down our throats. Glad somebody finally put engineering and math to paper. At a neighborhood BBQ I was talking to a neighbor, a BC Hydro executive. I asked him how that renewable thing was doing. He laughed, then got serious. If you really intend to adopt electric vehicles, he pointed out, you had to face certain realities. For example, a home charging system for a Tesla requires 75-amp service. The average house is equipped with 100-amp service. On our small street (approximately 25 homes), the electrical infrastructure would be unable to carry more than three houses with a single Tesla, each. For even half the homes to have electric vehicles, the system would be wildly over-loaded. This is the elephant in the room with electric vehicles. Our residential infrastructure cannot bear the load. So, as our genius elected officials promote this nonsense, not only are we being urged to buy these things and replace our reliable, cheap generating systems with expensive, new windmills and solar cells, but we will also have to renovate our entire delivery system! This latter "investment" will not be revealed until we're so far down this dead-end road that it will be presented with an 'OOPS...!' and a shrug. If you want to argue with a green person over cars that are eco-friendly, just read the following. Note: If you ARE a green person, read it anyway. It's enlightening. Eric test drove the Chevy Volt at the invitation of General Motors, and he writes, "For four days in a row, the fully charged battery lasted only 25 miles before the Volt switched to the reserve gasoline engine." Eric calculated the car got 30 mpg including the 25 miles it ran on the battery. So, the range including the 9-gallon gas tank and the 16-kwh battery is approximately 270 miles. It will take you 4.5 hours to drive 270 miles at 60 mph. Then add 10 hours to charge the battery and you have a total trip time of 14.5 hours. In a typical road trip, your average speed (including charging time) would be 20 mph. According to General Motors, the Volt battery holds 16 kwh of electricity. It takes a full 10 hours to charge a drained battery. The cost for the electricity to charge the Volt is never mentioned, so I looked up what I pay for electricity. I pay approximately (it varies with amount used and the seasons) $1.16 per kwh. 16 kwh x $1.16 per kwh = $18.56 to charge the battery. $18.56 per charge divided by 25 miles = $0.74 per mile to operate the Volt using the battery. Compare this to a similar size car with a gasoline engine that gets only 32 mpg. $3.19 per gallon divided by 32 mpg = $0.10 per mile. The gasoline powered car costs about $20,000 while the Volt costs $46,000-plus. So, the American Government wants loyal Americans not to do the math, but simply pay three times as much for a car, that costs more than seven times as much to run and takes three times longer to drive across the country.
In reply to #2
Whoever wrote your "repost" is not an engineer, or if the writer is they are intentionally being misleading with their data and is definitely intent on making an anti EV argument bolstered with exaggeration and falsehoods. Definitely not an honest argument.
The Volt test drive analogy to assumes that every trip int the Volt is 270 miles, and ignores what the Volt was designed for which is an average commute of under 25 miles round trip. I know Volt owners that rarely visit a pump.
Another example: Average US cost of a KwH from the grid is $0.13, more in some places than others obviously, so this person's cost calculation is about 10x reality.
Actually I consider using state electric vehicles as a backup supply for electric power systems to be a very good idea.
A few problems are easy to see. first obvious one is that the buses would be supplying DC voltage to an AC system. The differences were pointed out when Tesla and Edison went head to head. The DC power cannot be transmitted efficiently and thus needs to be converted to a synced AC 60 Hz via an inverter unit and would only supply a few homes each at best.
Public places as in emergency services, some hospital functions, police stations, fire stations could be supplied for lights and some basic function thru a power seeking automatic bus transfer switch.
I have yet to see how power can be backed up thru the transformers from home solar and wind units. It would take many synced inverters each with it's own transfer switch supplied with it's own bus to supply even a small portion of a grid.
I would recommend the new graphene capacitors as the battery for it's large storage capacity and very fast recharge ability that could be supplied by local wind turbines and / or solar panels that could be mounted on the bus.
You might consider talking to Newport News Shipbuilding on the details involved in the power handling that is done on submarines and ships.