Both energy efficiency and renewable energy can reduce greenhouse gas emissions and improve a home’s resilience during power outages. Cost effectiveness is another important consideration. Recent energy code changes have raised the question of whether renewable sources like rooftop solar photovoltaic (PV) panels can be substituted for energy efficiency measures like insulation and windows. But in the long run will it cost the homeowner more or less to make this substitution? This study compares the cost effectiveness of energy efficiency and an equivalent level of solar PV generation in the construction of new homes. We evaluate the net cost savings, amortized over 30 years, for cities in climate zones 2-6. In each city we find that homeowners would save money every month from energy efficiency measures whereas a solar PV system would actually cost them money.