A few weeks ago, I appeared before the City Council to introduce a groundbreaking proposal to require new, large-scale building projects to meet a “net zero” standard for greenhouse gas emissions.

The plan was initiated by members of Green Cambridge, a nonprofit organization dedicated to supporting local sustainability efforts. Together, we formed the Cambridge Committee for Net Zero Buildings and produced a zoning amendment petition that will put our proposal before the Planning Board and the council’s Ordinance Committee in the coming weeks.

Drafting of our petition was led by Mid-Cambridge resident John Pitkin and Kendall Square resident Quinton Zondervan, who also serves as chairman of our city’s Climate Protection Action Committee. In addition, we gathered input and feedback from a number of local architects, climate activists and neighborhood leaders.

The purpose of our proposal is simple: We want to mitigate the risks of extremely dangerous climate change.

Perhaps just as important, this initiative gives us an opportunity to set a positive example for collective action on the local level – an example that can be replicated by people in other communities and expanded upon in the future.

Working together, we have the capacity to steer our city away from fossil fuels and toward renewable resources such as wind, solar, geothermal and biomass. We do not have to wait for transformative policies to emerge from far-flung places such as Doha, Copenhagen or Washington, D.C. Instead, we can take bold action right now, putting into practice that old, familiar adage: Think globally, act locally.

The 80 percent solution

According to a 2009 Climate Protection Action Committee report: “Energy associated with building use is by far the largest contributor to greenhouse gas emissions in Cambridge.” In fact, roughly 80 percent of our emissions come from the daily operation of buildings. Given the urgency of the climate crisis, it makes sense to look at the zoning code as a mechanism for managing our carbon footprint.

In essence, our “net zero” petition says that future large-scale developments should not add to the concentration of greenhouse gases already present in our atmosphere.

This is more than just an efficiency standard – it’s an operational standard. To meet this challenge, developers are granted a high degree of flexibility through a range of options that are readily available and economically viable right now, in the year 2013.

First, developers are encouraged to design for maximum efficiency through proper choices of siting, massing, materials and equipment. Here in Cambridge, thanks to the tireless work of local leaders and concerned residents, requirements such as these are nothing new. They’re simply the logical extension of good design practices that have been put into place in recent years, such as the Stretch Energy Code (adopted in 2009 despite considerable reservations from the Chamber of Commerce) and the city’s own commitment to LEED efficiency standards (which dates back to 2004).

Second, on-site generation of renewable energy is also encouraged. This can be accomplished through the installation of photovoltaic and solar hot water panels, along with other options such as ground source heat pumps. Again, these technologies are widely available right now. Last month, the city broke ground on the 169,000-square-foot Martin Luther King Jr. school on Putnam Avenue – a “net zero” project that will generate about 60 percent of its energy needs through photovoltaic panels and geothermal wells.

Third, off-site energy may be obtained from renewable sources such as wind, solar or methane captured from landfills. This is key. Indeed, “net zero” will work for any size building because alternative energy providers are making renewables available on the grid right now. Instead of telling developers exactly how to shape their future projects, our plan simply calls for the implementation of best practices on-site while requiring that additional energy needs be fulfilled by suppliers who are verifiably not contributing to global warming.

Finally, as a fallback option, building operators may choose to buy Massachusetts Class I Renewable Energy Credits. These RECs are tradable, nontangible energy commodities certified by the commonwealth. They represent proof that a given quantity of electricity was generated by a renewable energy resource such as solar or wind.

Continuing with the example of the new MLK school, the city could meet our net zero requirement by entering into a cost-effective, long-term contract to buy renewable energy via the grid. At the school, it’s enough to supply the other 40 percent of total energy needs. If for some reason additional energy was required at a particular moment, conventional energy could be drawn from the grid on demand and RECs would be bought to offset the corresponding environmental impact.

Less expensive than fossil fuels

According to Ed Woll, chairman of the Energy Committee for the Massachusetts Sierra Club, the time for Cambridge to make the switch to renewables is now: “You will hear from developers that renewable energy is too expensive. Well, I don’t think that’s true. Given the studies we’ve seen, it’s actually less expensive than fossil fuels,” Woll said, testifying before the City Council in support of our petition last month. “This is innovative, but that’s what we in Cambridge are good at.”

This notion – that we’ve entered a new era of clean-tech innovation, rendering the old dichotomy between “the environment” and “the economy” as a thing of the past – was echoed last month by President Barack Obama when he addressed students at Georgetown University on the issue of climate change:

Convince those in power to reduce our carbon pollution. Push your own communities to adopt smarter practices. Invest. Divest. Remind folks there’s no contradiction between a sound environment and strong economic growth.

With our proposal for net zero buildings, we are working to answer the president’s call to action on what could easily be described as the most important challenge of our time.

Setting the precedent 

As city officials consider whether it makes sense to adopt the nation’s first comprehensive scheme for net zero development, it might help to reflect upon the fascinating story of how Cambridge became the first city in the world to implement a Recombinant DNA permitting ordinance in the 1970s.

Back then, as scientists were developing the process for splicing genes and creating genetically altered microorganisms, many people were worried about the prospect of virulent bugs escaping the lab and infecting the general population. When Harvard unveiled plans to renovate an existing building to accommodate this kind of genetic research in 1976, a local land use issue quickly escalated into a national story.

On the one hand were Cambridge residents – including many scientists – who asserted that the unknown risks associated with this field justified a new scheme of public oversight and accountability. On the other hand were those who decried government interference and worried that new regulations would limit academic freedom and discourage commercial enterprise.

That summer, the council convened a series of public hearings to address the issue. Both sides engaged in thoughtful, sometimes heated debate over the need for new regulations. In the end, the council voted to place certain limits and conditions on future genetic research – a bold move that had no precedent at any level of government.

Today, that fateful step is actually credited with helping to establish Cambridge as “the biotech capital of the world.” By being the first to grapple with emerging concerns and promoting a constructive dialogue among its residents, Cambridge was able to develop a mature understanding of the biotech sector, ultimately enhancing its appeal to businesses and residents alike.

Of course, the comparison between the rDNA ordinance and our net zero proposal is not meant to be exact. Nevertheless, the implication is clear: By taking action to restrict emissions and promote renewable energy, Cambridge can do its part to address the climate crisis while stimulating innovation and adding to our special character as a city.

Anyone wishing to learn more or get involved should visit our website at NetZeroCambridge.org.