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.

  • The Cost of Comfort: Climate Change and Refrigerants
    November 6, 2017

    Feature Article

    Refrigerants with very high global warming potential can negate the energy-efficiency benefits of many HVAC systems, including popular heat pumps.

  • Work Globally, Design Locally
    February 7, 2017

    Feature Article

    In today’s global economy, American architects work on six continents—but that doesn’t mean they should all have identical glass towers.

  • Heat-Pump Energy Recovery Ventilation Gets an Update
    August 2, 2017

    Product Review

    Build Equinox and Minotair Ventilation Inc. (MVI) have updated their heat-pump-based energy recovery ventilation systems, providing better control of humidity, heating, and cooling in a smaller footprint.

  • Are Cool Roofs Green? The Answer’s Not Black and White
    June 29, 2014

    Feature Article

    Roofing choices are complicated by heating tradeoffs, climate effects, and condensation, but proponents say reflective roofs still make sense in most climates.

  • Overcooled Offices Impair Thinking
    March 20, 2017

    News Brief

    New research shows a warmer setpoint combined with personal fans saves energy while maintaining occupant comfort and performance levels in tropical climates.

  • Façade as Ventilation: Moving beyond Open Windows
    March 8, 2017

    Product Review

    AirFlow Panels supply air and recover energy on commercial building façades, improving air quality while reducing energy and space requirements.

  • Passive Solar Heating
    June 29, 2012

    Feature Article

    Using the sun for most of a building's heating needs is in the DNA of green building. But in an age of superinsulation, does it still make sense?

  • No More Condensation on Chilled Beams
    February 7, 2017

    Product Review

    Semco’s Neuton pump module could simplify installation of chilled beams, eliminate condensation problems, and provide improved zone control.

  • Solar Thermal Hot Water, Heating, and Cooling
    August 30, 2011

    Feature Article

    By creating heat instead of electricity, solar thermal achieves three times the efficiency of photovoltaics at a lower price.

  • Buildings on Ice: Making the Case for Thermal Energy Storage
    June 30, 2009

    Feature Article

    Thermal energy storage uses ice to shift daytime cooling loads to nighttime, when electricity costs are lower. You may be able to reduce the size of chillers as a result, saving money and energy and lowering the environmental footprint of a building