Development and techno-economic evaluation of pathways to new construction net-zero energy houses in Nova Scotia, Canada

Abstract

The residential sector accounts for 17% of all energy consumption in Canada. Efforts to reduce this energy consumption and the associated emissions include the replacement of traditional housing with passive and net-zero energy house designs. These two concepts involve the decreasing of loads as much as possible through high-performance enclosures and high-efficiency mechanical and electrical systems as well as, in the case of net-zero energy buildings (NZEBs), offsetting these small loads with their own on-site renewable energy generation. The techno-economic feasibility of achieving NZEB status for a new construction, detached, single-family residences in Nova Scotia, Canada, is evaluated using a combination of energy modelling software to estimate annual energy use for proposed home designs as well as estimating the prospective monetary costs of proposed home designs. These energy use and cost evaluations are compared to a “base case”, an approximation of a current typical new construction four-person home. Based on cost and energy savings associated with each potential upgrade, a pathway to achieving a net-zero energy home is developed. This home can be developed in Nova Scotia at a 20% increase in initial cost with a payback period of 12 years when compared to the base case.