Burlington: the first city in the U.S to run on 100% renewable energy
Burlington, also known as a first city in the U.S to run on 100% renewable energy, a title they have been proud of since 2014. But how exactly do they do it? Is it really possible for a city to be powered entirely by renewable energy? It seems everyone wants to grow green these days. Green cars, green housing, small and green planet Earth models that you can hold in your hand, and green energy. And not surprisingly, what might be the greenest city in the US is located right in the Green Mountain State, Burlington, Vermont.
Back in 2004, the city was sourcing only about 25% of its overall generation from renewable sources. Made a decision to try to get to 100% is a pretty fast period of time since then and the city has gone all the way from 25% to more than 100% of the power sourced from renewable energy. Starting from the general overview of where the electricity in Burlington comes from, General Manager of Burlington electric department, Neale Lunderville says that they have the four main food groups for renewable power. Biomass, which is about 43% of our power, about 33% is from Hydroelectric power and the third major group is Wind which is 23% from the Georgia Mountain in Vermont and lastly, the little 1% is from Solar. Solar at the airport, in addition to they have homes and businesses with Solar inside the Burlington. That amounts for a very small per cent, but with all those together- Biomass, Hydro-electric, wind, and solar – that comprises the complete portfolio.
There is this one Winooski Hydroelectric facility on the Winooski River in Burlington, known as McNeil Plant. The woodchips are burned down in a boiler, which makes steam and the steam further goes down to a turbine that spins. The turbine is connected to a generator which further makes electricity that goes out on the line. This plant burns roughly around 75 tonnes of wood an hour to produce 50 Mega-watts of power. Throughout the year, the plant burns roughly around 400,000 tonnes of wood that is roughly equivalent to 600,000 trees a year. These are sustainably harvested woodchips so the foresters will go in and selectively harvest trees to allow for bird and bat habitats. Taking the tops and limbs of trees and grinding these into woodchips, transporting them.
efficiently, going back to the re-harvest areas to re-grow the fuel resource making it renewable. So, while burning the trees it is the most environmentally sensitive kind of way because regeneration of forests soaks up more of the carbon that is in the atmosphere. The technology right now doesn’t allow the city to run the grid on just solar power, or just wind power, or just hydro. Biomass power can be 24/7 power which is important and thus it is a lot better than burning oil, or even natural gas. So, as compared to coal and oil trees do seem to be a lot more renewable only if the forest grows back at the same rate as its being burned and Biomass should be carbon neutral.
In addition to carbon dioxide, there are other harmful emissions like nitrogen oxide and particulate matter into the atmosphere. There are a series of pollution control devices to regulate and limit what goes up the smokestack. The main job with the operator is to monitor continuously when the plant is online. All the ash is captured and there is a limit on opacities like the particulate matter. The ash generated by the boiler is saved and later used as a soil conditioner or a base for building roads. McNeil’s particulate nitrogen oxide emissions are well under state and federal limits. So, as a generator that gets its power from burning stuff, it is a relatively clean one. But outside of a pollution control and state and federal limits, it was hard to deny that these power plants just felt nice and clean.
But even though the power plants are clean and carbon neutral, there had been some other criticisms of Burlington’s 100% renewability claim. When Burlington electric goes back to the market to buy power is a residual mix of power from the grid, which could technically come from anywhere, including nuclear, natural gas or even coal. There are also at times, usually in the winter, when the plant has enough power to sell back into the market. But over the course of the whole year, the plant has enough power contracts to cover all of the power needs with the renewable resources. And in the future, when more renewable sources come online, there will be no need to rely as much on market power. In order to keep the power affordable, Burlington electric will also sell off a lot of power they produce in the form of renewable energy credits. By selling one renewable energy credits, and then taking what has been made from the sale, putting it back into keeping the rates low. It is the way to keep the renewability in place while at the same time allowing customers to benefit from the aggressive stance on renewable power. The key to really staying renewable is to cut down on the amount of power that you use. With the efficiency program, the city is working directly with the customers- both large as well as resident customers – to provide them with the package of incentives to help them move over to more efficient products.