Grocers have gradually bought into green initiatives, launching sustainability programs that focus on conservation of water and energy, reduction of truck traffic and zero-waste technology.

Whole Foods, for example, recently partnered with agribusiness Gotham Greens to build a 20,000-sq.-ft. greenhouse on top of a planned store in Brooklyn. The store will open in the Gowanus neighborhood in the fall.

Gotham Greens, which specializes in urban greenhouses, will build a rooftop farm with advanced irrigation systems that will use almost 20 times less water than conventional farming. The greenhouse will also feature enhanced glazing materials and electrical equipment that will reduce the overall energy demand, say Whole Foods officials.

Viraj Puri, co-founder of Gotham Greens, says the rooftop greenhouse will cut down on travel time  for customers (and accompanying vehicle emissions) to just a short walk for fresh produce. “We’re thrilled with this partnership and to be a part of the growing national movement of farmers and food producers committed to providing customers with high-quality, responsibly-produced food,” he says.  

Kroger, through its Ralphs/Food 4 Less brand on the West Coast, has begun disposing of its waste food by using a new clean-energy system at its Los Angeles distribution center in the Compton neighborhood. The company takes all the food waste from about 330 stores in California and Nevada–about 150 tons per day–and trucks it to Compton.

The new Kroger Recovery System uses anaerobic digestion to transform the food and food-processing effluent into renewable biogas to power about 20 percent of the 650,000-sq.-ft. distribution center. The Kroger system is designed and operated by FEED Resource Recovery Inc., a clean technology company based in Boston. The company was founded in 2007 to find zero-waste solutions for the food industry

“We still donate unsold food to local shelters, but that which can’t be donated, and even the packaging, can go in the bin,” says Kendra Doyel, a vice president with Ralphs. “Dilution turns it into a sort of slushy milkshake, and the digestion process turns it into gas, with very little byproduct. The process generates enough energy to power about 2,000 homes,” she says.

This unique project is just part of the Cincinnati-based Kroger’s national sustainable initiative. With about 2,424 stores in 31 states, the company is trying to meet increased electricity savings, recycling and zero-waste goals. For example, the grocer has reduced overall energy consumption in its stores by 31 percent since 2000, enough electricity to power every single-family home in Columbus, Ohio, for one year, Kroger’s Chairman/CEO David Dillon noted in the company’s 2012 annual sustainability report.

Kroger tries to meet its goals by not only engaging employees in the green culture, but also by using social media, store placement and outreach to encourage customers to make green choices in their everyday purchases. The company isn’t alone, as a number of grocers have launched campaigns to provide better sustainability information to shoppers.

The Manomet Center for Conservation Sciences, based in Plymouth, Mass., recently started its Grocery Stewardship Certification program for grocers, which includes the requirement to teach customers how to buy green.

Hannaford Supermarkets, with about 93 stores in the New England region, is the first chain to go through the certification process. Peter Cooke, a Manomet program manager who developed the process, says the certification of just a dozen stores by reducing energy consumption, water use, waste and other products would mean those properties would see annual savings of 3.6 million gallons of water, 2 million kilowatt hours of electricity, 12 million pounds of solid waste and a reduction of 103 million pounds of greenhouse gas emissions.

“Grocery stores have an incredible opportunity to make reductions in areas such as energy-efficient lighting, reducing waste through recycling, cutting back on hazardous cleaning materials and even water use at the store,” Cooke says. “Along with implementing those changes, the store also has an opportunity to influence customers on sustainable decisions on products they buy, through enhanced displays and other methods. The market research shows that many customers today are looking at how to be more environmentally friendly themselves, and their local market can serve as a great example.”