Super-insulate or use renewable technology? Life cycle cost, energy and global warming potential analysis of nearly zero energy buildings (NZEB) in a temperate oceanic climate

This paper presents the outcomes of a number of case study buildings in Ireland, which focus on the life cycle cost and environmental analysis (using energy and global warming potential as indicators) of NZEBs using various heat sources, such as a gas boiler, biomass boiler, a domestic gas fired combined heat and power unit, heat pump and renewable technology. With the de-carbonisation and increased efficiency of the electricity grid, the low global warming potential (GWP) emissions of biomass fuels and the depletion of fossil fuels, future buildings should be (i) designed and constructed to be super-insulated with high air-tightness performance resulting in minimum heating requirements and (ii) operate with heating systems that have low impact on the natural environment, such as a biomass boiler or heat pump.