Carbon Free Boston (CFB) is the city’s initiative to reach carbon neutrality by the year 2050. For about a year, CFB researchers have been studying the pros and cons of different paths to that goal. Their report, due out later this fall, will estimate the amount of carbon reduction, the cost, and the environmental justice impacts of many potential ways to reduce greenhouse gas emissions. The city will use this information to prioritize the best strategies.
In June, CFB posted a preliminary report listing some of the options under consideration. Using this document and other information sources, BostonCAN has been familiarizing itself with potential strategies in the energy, transportation, and buildings sectors. Our purpose has not been to draw conclusions ahead of the research results, but to understand the choices and related issues so that we are prepared to respond after the report is released. Three of our Action Team meetings this fall feature presentations on carbon policy. The first of these, on the energy sector, was delivered on September 27 and is summarized below.
By the “energy” sector, CFB means activities involved in the production of electricity. Options under study for this sector fall into four categories: district energy policy, gas policy, in-boundary renewable energy policy, and out-of-boundary renewable energy credit and purchase.
A district energy system provides power efficiently to a group of buildings. An example is the Medical Area Total Energy Plant (MATEP) in the Longwood Medical Area of Boston. Types of district energy systems include microgrids (small electric grids that can connect to the regional grid or operate independently), combined heat and power systems (where heat generated as a byproduct of electricity is captured to warm buildings), and trigeneration systems (which produce electricity, heating, and cooling). Potential policy options include building more district systems, forcing the retirement of ones that run on fossil fuel, and reducing related regulatory barriers.
CFB’s preliminary report raised only two gas policy options: renewable gas supply and natural gas leak mitigation. “Renewable” gas refers to hydrogen and biogas. They are “renewable” in the sense that we can produce more, but they still emit greenhouse gases. Natural gas leaks are problematic because they waste resources, release the greenhouse gas methane into the air, poison plants and animals, and increase the risk of explosions.
In-boundary renewable energy refers to “green” electricity that is generated within Boston. In an urban setting, the most practical source is solar panels. Two ways the city could bring more solar to Boston would be to mandate or incentivize building owners to install it or to put it on municipal buildings.
A related option is to address the net metering cap, a state policy that currently inhibits the development of large solar projects. Under net metering, solar owners receive credits on their electric bills whenever they are producing more power than they are using (picture a sunny day with few appliances turned on). Net metering helps shorten the payback period for solar. If an owner runs a negative balance, the excess credit can be applied to another electric account. However, Massachusetts limits (caps) the amount each electric company has to pay for net metering. While most residential installations are small enough to qualify for net metering despite the cap, new larger arrays are ineligible once the cap is reached. An example of how this discourages larger projects is the experience of Bethel AME Church in Jamaica Plain. They planned to put many solar panels on their church and assign the excess power to congregation members. However, they had to settle for a smaller system than they wanted because of the cap.
Out-of-boundary renewable energy is “green” power that is generated outside of Boston for the benefit of Boston users. There are several ways that people can get renewable energy without buying the generators that produce it (e.g., solar panels, wind turbines, or hydroelectric plants).
- Community-owned renewable power means that a group of people own a “green” generator together. Community-owned renewable power can be located in- or out-of-boundary.
- Power purchase agreements (PPAs) and Renewable Energy Certificates (RECs) are two ways of having green energy without buying or chipping in for the equipment. PPAs and RECs differ because the price of renewable energy is split into two parts: the actual energy, and the fact it is renewable. In a PPA, people buy the electricity itself from a renewable source. RECs are documentation proving that the owner of a “green” generator has produced a certain amount of renewable energy. When people buy RECs, they get the right to say that they are using green energy even though their power really comes from the grid, because they are providing financial support for renewables.
- Carbon offsets allow an entity (usually a business or government) to pay another entity for the right to claim an amount of carbon reduction actually achieved by the second party. For example, if Boston and another city both have carbon reduction targets, and Boston is falling behind while the other city is ahead, Boston can buy carbon offsets from the other city. Offsets are intended to allow for the fact that some entities have more barriers to carbon reduction than others.
- Providing clean power purchasing options to consumers is another thing that a city can do. Boston’s forthcoming Community Choice Energy program is an example.
- The city could also provide financial incentives for on-site and off-site renewable generation. This could take several forms, including lower property or sales taxes.
In the days to follow, we will publish summaries of BostonCAN’s presentations on CFB options in the transportation and buildings sectors. Stay tuned!