Tackling Climate Change One City at a Time. Is Net Zero the Right Approach?

Boston, modestly referred to these days as the “city of champions” by its inhabitants, is now championing net-zero buildings.

The new initiative, which will be added to the city’s Climate Action Plan, “will require new city buildings to either cause no emissions of carbon — through a combination of efficiency improvements and use of renewable energy — or to offset any emissions, which are caused by oil and gas used for heating and electricity generation, with carbon-reducing investments.”

Boston is the latest major city to adopt net-zero targets, joining New York, Los Angeles, London, Madrid and several others. The World Green Building Council defines a net zero carbon building as a building that is highly energy efficient and fully powered from on-site and/or off-site renewable energy sources.

Not everyone believes that creating net-zero targets is the best approach. The Economist, in a recent article titled “The Right Way to Measure Carbon Emissions,” said that although net-zero targets are a step in the right direction, they focus only on carbon produced within the target-setting entity’s borders (or buildings); they do not include carbon that’s related to goods consumed in the target area but produced elsewhere. The Economist noted that a quarter of all global emissions of carbon are tied to trade flows, meaning the net-zero really isn’t, well … actually zero.

Another important consideration for net-zero programs should be addressing the carbon emissions from existing buildings within a target area. Most programs focus on new construction, which, while important, excludes the vast majority of the building stock. According to the U.S. Department of Energy, roughly half of U.S. commercial buildings were built before 1980.

“Today’s zero energy programs largely focused on new construction leave out the largest percentage of our buildings,” said Jennifer Thorne Amann, Buildings Program Director, American Council for an Energy Efficient Economy (ACEEE). Amann and the ACEEE are strong advocates for ultra low energy buildings (ULEBs), also known as zero-energy ready. According to Amann: “Our research shows that many existing buildings can be ULEBs with completion of deep retrofits.” So, how do we push people toward creating ULEBS? “We’re going to have to get to mandates to meet energy and carbon goals,” said Amann. “There’s no way we’ll see widespread transformation of our existing buildings without them.”

Boston’s plan, like most others, is focused on new city-owned buildings, but they recognize that retrofitting large private buildings will be crucial to reaching its goal of being carbon neutral by 2050. For its part, Los Angeles's Sustainability Plan mandates that new buildings be zero-emission by 2030 and existing buildings by 2050. In New York, the goal is to reduce greenhouse gas emissions from buildings 40% by 2030 and 80% by 2050. Existing buildings over 25,000 square feet in size will have to implement energy efficiency measures to hit a mandated reduction of 40% by 2030 or they’ll be assessed a penalty.

At Metrus, we believe there’s significant value in setting net zero targets. While we see the gaps in current programs, we also believe it’s acceptable to walk before we run. Net zero targets for new construction should be viewed as the first phase, the warm-up lap if you will, but we need to quickly accelerate the pace of programs to include existing buildings. To properly fight climate change, this means setting ULEBs as the target. Aggressive timelines for adoption with penalties for non-compliance are needed. We believe the market will respond to these types of clear signals and know that buildings owners can avail themselves of numerous third party financing and energy efficiency services options to get the job done.