Yolanda Fernández-Nava

The aim of this study is to estimate the environmental impacts associated with modernization measures that improve the energy efficiency of an office building listed as of cultural interest and located in northern Spain, a region with an Atlantic climate. European Climate Action for 2020-2030 sets a long-term goal of achieving neutrality of greenhouse gas emissions and towards the end of 2019 the Spanish Government presented its Integrated National Energy and Climate Plan. It is of interest to the international audience to know how energy policies can affect decisions on building retrofitting to improve sustainability: reduction in energy consumption, climate change and other environmental impacts. A life cycle assessment was carried out for the retrofitting of the building envelope and different energy supply scenarios: only electricity from the electricity mix (scenario of reference that of 2018, and decarbonisation scenarios proposed for 2020 and 2030), and the installation of heat pump and photovoltaic panels. The impacts will decrease 40% for Global Warming Potential and 15% for Cumulative Energy Demand in 2030 with respect to the reference scenario. These reductions will further increase up to 54 and 61%, respectively, if photovoltaic panels and a heat pump are implemented.

The use of lightweight concrete for the construction of single-family houses has become increasingly popular in Spain. In this paper, single-family houses with different shape factors and window-to-wall ratios are analysed from both a thermal and environmental perspective using Passive House Planning Package (PHPP) software to calculate the energy demand. The study has been carried out for different Atlantic microclimates (coastal, inland, and mountain) in northern Spain. What most affects the thermal energy used for air conditioning is the variation of the microclimates, so the study focuses mainly on this aspect. Operational energy for heating has decreased greatly via the use of high degree of insulation and hence the next task is to decrease the total energy consumed taking into account the embodied energy. Impacts on Primary Energy and Global Warming Potential are calculated using a cradle-to-grave approach. The energy use for heating and domestic hot water is analysed for different thicknesses of insulation under three energy supply scenarios: electricity only (for 2018 and with the Spanish decarbonisation plan for 2030); heat pump plus electricity; and natural gas boiler. Even for houses with a good level of insulation, the ratio of operational-to-total impacts varies significantly: from 46% to 87% for primary energy and from 31% to 75% for global warming potential, depending on the shape factor of the house, the microclimate and the heat supply scenario. By applying future environmental policies, electricity can become a more environmentally friendly option than natural gas.

Climate change is associated with global warming. This paper discusses the environmental impacts of the decarbonisation plan proposed by the Spanish Government, comparing the current situation with those foreseen for 2020 and 2030. Furthermore, climate change will vary the thermal demands of buildings. The paper thus investigates the heating and cooling demands of a type of single-family house located in eight Spanish cities with very different climates and altitude. The combined effects of the decarbonisation plan and climate change are analysed based on the environmental impacts caused by the electricity required to meet thermal demands. Both effects led to a reduction of the damage in the categories Human Health (59–68%), Climate Change (57–67%) and Resources (54–65%). However, the damage to Ecosystem Quality will increase (5–28%) as a result of the greater impact on this damage category from the energy production scenario for 2030, although thermal requirements in households will decrease.