LCA Analysis of Renewable Domestic Hot Water Systems with Unglazed and Glazed Solar Thermal Panels

The paper presents a from-cradle-to-grave LCA (Eco-Indicator 99, Egalitarian Approach) study for two domestic solar hot water systems (DSHWS): a traditional one with glazed panels and a system with unglazed solar collectors. Both systems are coupled with a 300-liters storage tank. The performed LCA returns an EI99 equal to 198.19 for the traditional glazed DSHWS and equal to 18.28 for the unglazed one. For each DSHWS the energy, CO2 and economic pay-back times were calculated for three different locations (Rome, Madrid and Munich) in order to take into account the influence of local climate on the solar panels yields. The payback times took as basis of comparison two competitive technologies: the natural gas and the electrical boiler.