Heating & Cooling

District heating systems provide economies of scale in large cities like Copenhagen.

Photo: Bill Ebbesen. License: CC BY 3.0.


Energy-efficient HVAC design is a fundamental of green building, for good reason:

  • The scale of the issue: HVAC is responsible for more than a third of energy use in commercial buildings in the U.S.

  • The scale of returns: Smart designs can easily save upwards of 40% of that energy, often with strategies that offer instant or short “payback.”

  • The human impact: Discomfort from spaces that are too hot or too cold, and lack of adequate ventilation, are an epidemic. Good design that fixes these problems supports healthier, more productive occupants.

Don’t make the all-too-common mistake of thinking of HVAC design separately from building envelope design. Over-glazed buildings lead to oversized mechanical systems, increasing costs on both fronts. A tight, well-insulated envelope may cost a bit more but can pay for itself with less mechanical equipment.

  • Cold Climate Heat Pump Redux

    Product Review

    The two-stage high-capacity cold-climate heat pump that was introduced in 2004 and then discontinued in 2005 is back, and from more than one company.

  • Climate Energy Brings Combined Heat and Power Home

    Product Review

    The idea of combining electricity generation with the production of useful heat-referred to as combined heat and power (CHP) or cogeneration-has long been attractive. Now, after many false starts, a viable residential-scale CHP system is about to enter the market.