PV or Solar Hot Water? New Construction Law in Hawaii Allows for Variance

Hawaii is making great strides towards the goal of achieving 70% clean energy by the year 2030. Significant progress in reaching this milestone will surely come from a new, clarified construction law that requires a renewable energy technology on all new residential construction – whether it be Solar Water-Heating or Photovoltaics.

Though this new law is a great stride toward sustainability, there is some confusion amongst Hawaii homeowners and homebuilders as to what the legislation truly requires. The mandate has been generally publicized as endorsing (and requiring) only solar water-heating on new homes, but upon closer analysis, photovoltaic arrays can also satisfy the legislative requirements.

Back in June of 2008, Hawaii enacted legislation, SB 644, with the intent to require solar water-heating systems to be installed on all single-family new home construction, with a few exceptions.

This legislation had several errors that were corrected by legislation passed during the 2009 legislative session. In June 2009, HB 1464 was signed by the governor and addressed the errors in the previous solar water-heating requirement.

As of January 1, 2010, building permits may not be issued for new single-family homes that do not include a solar water-heating system.

BUT, homebuilders can now substitute Photovoltaics for solar water-heating through what is called a “variance.”

Solar water heating has proven to be a tremendously valuable technology in the past, but there are only a few uses for solar-heated hot water in your home – laundry, dishes and bathing.  Conversely, solar electricity can power your TV, run your A/C, cook your dinner, wash and dry your clothes, charge your cell phone, power your computer, clean your house and more! As Photovoltaic technology has improved in efficiency and costs have come down, Sunetric believes that in nearly all cases, an investment in a photovoltaic system will provide better return than one in a solar water-heating system (Click here to view our white paper).

We know heating water uses lots of electricity, so we recommend you use the newest heat pump technologies that are incredibly efficient, easy to install and use very little electricity.

So how does the variance work?  Well, the State energy resources coordinator may provide you with a variance for this requirement if:

  • Installation is impracticable due to poor solar resource;
  • Installation is cost-prohibitive based upon a life cycle cost-benefit analysis that incorporates the average residential utility bill and the cost of the new solar water-heating system with a life cycle that does not exceed 15 years;
  • A renewable energy technology system is substituted for use as the primary energy source for heating water; or
  • A demand water heater device approved by UL is installed; provided that at least one other gas appliance is installed in the dwelling. (A “demand water heater” means a gas-tankless instantaneous water heater that provides hot water only as it is needed.)

The legislative intent is that the demand water heater provision should only apply if the variance applicant is the individual that will be paying for the energy costs (the homeowner). A variance is automatically granted if not approved within 30 days or if a Hawaii licensed architect or mechanical engineer attests to one of the allowed exemptions.

To get a variance you must submit a Request for Variance from Mandatory Solar Water Heater in New Single-Family Residential Construction form.  Under section IV. Reason for Variance request, you may check the “A substitute renewable energy technology is used…” and the photovoltaic line as well.

The form takes approximately one and half weeks to approve under “normal circumstances,” max of three weeks with furlough Friday backups.

Dean Masai, DBEDT Energy Office, can be reached at 587.3804 with any questions you may have.  His office is available on the web through DBEDT, then Energy, and the Variance form is found almost at the bottom of that page.

Download the Request Variance form here.

You only have so much space on your roof, so make good use of it.  Use it to create electricity.