According to a new report from The American Council for an Energy Efficient Economy (ACEEE), while energy efficiency and rooftop solar photovoltaic (PV) work together to provide complementary energy and carbon reductions in new homes, the former should be prioritized over the latter if a choice needs to be made for budgetary reasons.
Christopher Perry, an ACEEE senior analyst and an author of the report, wrote in an ACEEE blog post explaining the report, "When budgets are tight, energy efficiency is more cost effective." According to the report, while energy efficiency can deliver $4 to $32 in net savings per month, rooftop solar can cost up to $14 a month.
Thus, the best way to promote the growth of energy efficiency is to focus on effective building codes and standards. "For the U.S. residential sector, building codes like the International Energy Conservation Code (IECC) and voluntary labels like ENERGY STAR provide cost-effective guidance for insulation, windows, lighting, and heating and cooling equipment to construct efficient and sustainable homes,” stated Perry.
ACEEE found that the energy efficiency measures contained in these and other codes and standards are more cost-effective than an equivalent amount of energy generated from solar photovoltaic panels. "Based on these results, we conclude that new homes must first be built efficiently for maximum cost effectiveness," stated Perry. "Solar panels can then be added to further reduce carbon emissions and help homes meet zero-energy targets."
In fact, while energy efficiency should be the first priority, solar should always remain a serious consideration. For example, the report noted, when solar PV is paired with battery storage, it can provide a homeowner with electricity during a power outage. In addition, Perry noted, "[I]nstalling rooftop solar panels is a great way to signal a clean-energy commitment to the world, while efficiency measures like insulation and efficient water heaters typically remain hidden."
In sum, he stated, "Once a home achieves compliance with energy codes through energy efficiency, then solar can help meet the remaining energy load."