Consumers Energy has pledged to emit net zero carbon from production and consumption of natural gas, including customers and suppliers, by the year 2050.
The pledge is an overt acknowledgment that although burning natural gas is cleaner than burning coal, it still creates greenhouse gas emissions that drive climate change.
"Natural gas," is the utility industry term for methane.
The utility says achieving net zero emissions means eliminating the impact of emissions traced to the burning of natural gas by customers, as well as greenhouse gas emissions caused by natural gas suppliers who produce and transport natural gas to Consumers Energy’s system.
“Natural gas is safe and affordable and now it can be even more clean,” President and CEO Garrick Rochow said. “We’re making historic, industry-leading changes to protect our planet. This commitment is another step in leading the clean energy transformation for Michigan.”
The Consumers plan may rely on a number of strategies to achieve the net zero goal, including:
Carbon offsets: These can include programs such as preserving and increasing Michigan forests. Trees are excellent natural sequesters of carbon.
Renewable natural gas, or RNG: Methane is produced from organic wastes in landfills, and it can be captured and burned just like methane from traditional natural gas acquisition.
Energy efficiency: Energy efficiency programs can reduce the amount of methane customers need to heat their homes.
Emerging technologies: Potential solutions include using hydrogen to produce energy, capturing and permanently storing carbon emissions from natural gas combustion and using hybrid natural gas and electric heat pump systems to heat homes and businesses.
Charlotte Jameson is Chief Policy Officer for the Michigan Environmental Council. She said Consumers Energy should get credit for taking an important step, but she says the utility will need to hold itself accountable since the pledge is voluntary.
"I am going to remain skeptical about these sorts of announcements and how credible it is that we can hit the targets for greenhouse gas emissions reductions that they've outlined," she said.
Jameson said using offsets, such as investing in carbon sequestering projects like preserving forests and tree planting, can too often become simply an accounting gimmick. She said underground carbon sequestration is a largely unproven technology - and extremely costly, requiring the addition of massive infrastructure.
But Jameson was enthusiastic about the potential of energy efficiency to reduce the need for methane gas for heating, as well as the prospect of increasing the state's reliance on air source heat pumps.
Air source heat pumps are powered by electricity, using technology to transfer heat from outdoor air to indoor air in cooler months, and reversing the process to transfer heat from indoor air to outdoor air in the warmer months.
When the electricity running the heat pump comes from renewable energy sources such as wind and solar, the devices can provide heating and cooling with almost no greenhouse gas emissions.
The technology is most effective at 30 degrees or higher, but recent advances have made heat pumps increasingly useful in cooler regions.
"That's how we're going to decarbonize buildings, getting off the gas system entirely," Jameson said.
Consumers Energy says the new pledge is in addition to its previous goal of net zero methane emissions from its natural gas delivery system by 2030.
The utility says it has already reduced methane emissions from its natural gas distribution system by about 15 percent.
Consumers Energy is one of Michigan Radio's corporate sponsors.
