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U.S. Department of Energy Energy Efficiency and Renewable Energy

Frequently Asked Questions (FAQs)

Read the frequently asked questions and their corresponding answers to learn more about the DOE's Windows Volume Purchase.

What is the strategy behind a windows volume purchase?

A volume purchase is a form of market transformation. In order to overcome the principal cost barrier of high performance windows, the DOE Building Technologies Office (BTO) is employing a three-pronged strategy to increase demand and lower costs.

  • BTO is making production engineering awards to window manufacturers to drive down the cost and improve the performance of high performance windows.
  • BTO is also working to establish more stringent ENERGY STAR® requirements.
  • In order to increase market demand, BTO is organizing a volume purchase of high performance windows.

What are the barriers to an high performance windows market transformation?

The principal barrier to widespread market commercialization of high performance windows is cost. The Department of Energy is working with industry and potential buyers to lower cost and make these energy efficient products more readily available. Additionally, high performance windows can be somewhat marginally thicker and heavier than traditional window.

Why a high performance windows volume purchase now?

Windows in the U.S. account for 30% loss of building heating and cooling energy, representing an annual impact of 4.1 quadrillion Btu (quads) of primary energy. Windows have an even larger impact on peak energy demand and on occupant comfort.

In cold and mixed climates, high performance windows offer significant energy savings compared to other high performance windows and are cost effective when produced in volume.

Lifetime (20 yr.) savings per 3' x 5' window with U-factor 0.22
Assuming a 3% discount rate after adjusting for inflation

Horizontal bar chart with marginal cost (MC) and marginal savings (MS) per window for 3 window types in Boston, MA: a hi-volume R-4 window has a MC < $50 and MS > $60; a current (low-volume) R-5 window has a MC of ~ $120 and MS slightly less; a hi-volume R-5 window has a MC of ~ $60 and MS of ~ $110.

Horizontal bar chart with marginal cost (MC) and marginal savings (MS) per window for 3 window types in Minneapolis, MN: a hi-volume R-4 window has a MC < $50 and MS > $50; a current (low-volume) R-5 window has a MC of ~ $120 and MS < $100; a hi-volume R-5 window has a MC of ~ $60 and MS of slightly < $100.

Horizontal bar chart with marginal cost (MC) and marginal savings (MS) per window for 3 window types in Spokane, WA: a hi-volume R-4 window has a MC < $50 and MS > $50; a current (low-volume) R-5 window has a MC of ~ $120 and MS < $100; a hi-volume R-5 window has a MC of ~ $60 and MS of slightly < $100.

Although presently R-5 windows tend to be niche products that can be cost-prohibitive, there is a large energy and cost savings potential from volume demand and supply.

Is there an overview of the program?

The following presentationPDF provides background and summary information on the DOE Volume Purchase Program.