Since our last report, we have continued to invest in our landfill-gas-to-energy systems by installing over 150 gas collectors and 40 acres of cap across nine locations. Our energy development efforts at the remaining three active target landfills have been delayed by challenges such as a lack of grid capacity and low natural gas and electricity prices.
Energy recovery fits into our broader resource renewal vision. In the coming years, we will continue to advance landfill gas to energy, anaerobic digestion, landfill heat recovery, solar energy, and innovative new forms of energy capture at our facilities.
For a few years now, an innovative geothermal heat loop installed in the base of the landfill has been providing warmth to the maintenance shop, saving over 1,000 gallons per year of heating fuel. More recently, the North Country team has added a small on-site greenhouse, which grows fresh produce and serves as a classroom resource for local elementary school students.
The greenhouse is now a stop on the landfill tour, inspiring visitors to stop and think about all forms of waste and the many innovative new ways we could transform waste into resources.
This is only the beginning. The North Country team has its sights set on an even more exciting opportunity. They're working on upgrading the site's landfill gas into renewable natural gas (RNG) suitable for pipeline injection and vehicle fuel. The project is working its way through approvals and is slated to come online in 2019.