Cost-benefit analysis of nZEB energy efficiency strategies with on-site photovoltaic generation

Many studies on the deployment of and investment in renewable energy (RE) technologies have focused on job creation associated with energy production at the macroeconomic level and across renewable energy technologies. We propose another perspective, the use of solar photovoltaic (PV) technology to attain a nearly zero-energy building (nZEB) class. The aim of this research is to investigate the costs and benefits for private and public entities when constructing nZEB or adopting nZEB policies. A quantitative research approach is taken when modelling required PV capacities, net present cash flows, subsidies, and job generation. Findings show that at current electricity tariffs and solar PV system capacities and production levels, single family houses, apartment buildings, and other building types require 0.044 €/kWh, 0.037 €/kWh, and 0.024 €/kWh, respectively, in government subsidies on energy sold back to the grid. Office buildings were profitable without the subsidy. In this study, we argue that investments in RE, specifically, PV technology, will bring in approximately 2.1 M€ of additional revenue to the Estonian government over a 20 years period as tax return overruns subsidies. However, nZEB investments are expected to become cost-optimal without subsidies, due to the increasing efficiency and decreasing costs of PV systems.