[Edit: a previous version of this story incorrectly stated that PG&E was controlling the charging of customer’s electric cars via BMW’s telematics system. Instead, BMW is controlling the charging of customer’s cars directly using the telematics system. We have modified the article below to correct this error and appologize accordingly.]
One of the criticisms laid at the feet of electric car owners is that their vehicles are only as clean as the source used to produce the electricity that their cars rely on. And in a very simplistic way, those critics are right, at least on paper: an electric car charged using electricity generated from a photovoltaic solar array is far greener than the huge emissions produced as a consequence of generating the same amount of electricity using a coal-fired power station.
The reality is of course a little tougher to discern. Utility companies produce their electricity using a variety of different generation sources, each with their own carbon footprint. Depending on the weather conditions and grid demand, an electric car charged using the same charging station may have a lower carbon footprint on one day than another. Similarly, an electric car charged during low-demand periods tends to have a smaller carbon footprint than one charged during peak demand periods.
But despite some general rules that can help ensure your car is charged using greener electricity from the grid — such as charging outside of morning and evening rush hours or delaying charging to night time — it’s difficult to know exactly when a good time is to charge in order to have the smallest carbon footprint.
In the world of the Internet of Things and the Smart Grid, that’s changing, which is why BMW and Pacific Gas and Electric (PG&E) are pushing forward with the second phase of a long-term partnership investigating how to make electric vehicle charging as clean and as green as possible.
Announced this morning, the partnership will take the form of a pilot program across PG&E’s service area in Northern California. Participants (BMW i3 and BMW i8 owners who sign up for the program) will be able to opt to have their car charging patterns remotely controlled by
PG&E BMW via the telematics system built into their cars rather than rely on an arbitrary charge timer or the usual charge upon plug-in practice many owners still prefer.
The goal? To use Smart Grid technology to help lessen demand on the electrical grid during peak demand periods by pausing electric car charging when demand is high and shifting charging to periods where electrical grid demand is less. All at the same time as making electric car cheaper and greener for customers.
To ensure that customers aren’t left without a charged battery when they need it, participants can either opt out of the system temporarily, charging their car immediately for the next trip, or they can request that their car is charged by a specific time so that they can leave for their next planned appointment with a full battery.
Of course, this isn’t the first time we’ve heard of such a project being used. We’ve seen similar projects launch before in both the U.S. and Europe, where automakers, charging equipment manufacturers and utility companies have all worked together to study the benefits of using Smart Grid technology to control vehicle charging time. Some charging station products — like the JuiceBox from emotorwerks — even offer similar functionality using their own Internet-connected services.
It’s all well and good to have your charging controlled by an external load-aware service — but how much of an impact will the project have on emissions? Well, if the results of the first phase of BMW’s Smart Grid trial with PG&E are any indication, an impressive amount of carbon dioxide could be prevented from entering the atmosphere every year.
During its first fifteen-month phase of the trial in which BMW offered customers incentives to delay charging their car until off-peak demand periods where energy generation was greener, a total of just under 100 participants signed up. During the trial, BMW says a total of 19,000 kilowatt-hours of electricity was shifted from peak demand periods to low-demand periods.
While we can’t say for sure what the net carbon footprint change was of shifting that charging to low-demand periods, it’s worth noting that the carbon footprint of a coal-fired power plant equates to around 2 pounds of CO2 per kilowatt-hour of electricity generated. If we assume shifting that generation enabled those cars to be charged from renewable sources of power instead, the savings equate to 19 tons of CO2 not entering the atmosphere.
Do you like the idea of using Smart Grid technology to control when your car charges? Or do you worry that you’d be left high and dry without a full battery pack when you needed it.
Leave your thoughts in the Comments below.
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