With 30 miles of district heating steam pipes, Boston has one of the most extensive systems in the country. Veolia Energy, the largest district provider in the area, services 240 buildings—or 44 million square feet of space—in the Boston Metro area. Recently the GenOn Kendall Station combined heat and power facility connected to the district heating system. In 2008, the EPA issued a permit allowing the station to install a second pipeline across the Longfellow Bridge. Once constructed, this pipeline will save an estimated 275,000 short tons of carbon—the equivalent of taking 50,000 cars off the road—and will provide twice as much steam to Boston metro area customers.
We talked to Bill DiCroce, Executive Vice President and Chief Operating Officer of Veolia Energy, and Jim Hunt, Chief of Environment and Energy for the City of Boston, to find out about district heating and its contribution to Boston’s climate change planning.
Bill DiCroce explains the efficiency created by district heating and cooling systems. District systems connect multiple energy consumers to centralized energy sources. Combined heat and power (CHP) facilities burn fuel to produce electricity and steam, which is transferred to consumers using underground pipes. Waste heat from power production is recycled into usable thermal energy rather than being released back into the environment, increasing fuel efficiency and minimizing environmental impact. According to the International District Energy Association (IDEA), combined heat and power facilities operate at about twice the fuel efficiency of traditional electric-only generating stations.
Jim Hunt comments that district energy systems are great for Boston, where 76% of greenhouse gas emissions come from buildings. Connecting buildings to a system that uses less fuel and produces less harmful emissions is a promising path to mitigating the impacts of climate change. Using off-site resources also frees up valuable on-site space where boilers, chillers, or other energy systems would have been. In addition, buildings earn alternative energy credits by using CHP sources under the Green Communities Act, which may make them eligible for government incentives. Leading by example, Boston currently uses district heating to service its 250 municipal buildings, which uses 200 million KW of electricity annually.
We asked Mr. Hunt and Mr. DiCroce why Boston and other cities don’t use district heating and CHP systems more, given the energy savings they allow. They explained that while district heating and cooling systems have lower ongoing operation and maintenance costs, building or expanding district heating systems is extremely capital intensive. Putting piping in is very expensive, and extremely difficult to do underneath an established infrastructure. If it was not included in the original construction, it makes the most sense to add district heating when developing new areas or doing a major rehabilitation of an old area.
There is a lot Boston needs to do before it can catch up to district heating giants like New York City, whose 100 mile system serves over 18,000 buildings. Among his current strategies to augment the system in Boston, Mr. DiCroce knocks on developer’s doors when they are building new projects to suggest they connect to the district system. With decreased environmental impacts and increased energy efficiency, district heating is a smart option for buildings because it delivers what he calls “the most bang for your buck” in heating, cooling, and electricity.