• Energy Research
• Restricted close
• Open Source close
• 7. Clean energy close
• CH close
• FR close

In this article is presented the preliminary evaluation of the performance of radiation transmission of glass block, used in support of photovoltaic cells, investigating different internal surface points of the block, which are subject to different shading during daylight hours. The aim is to establish how the edging setting, the only opaque element, can reduce the amount of light radiation during the day, introducing in this way a reduction of efficiency of the entire generation system. The generation system can be based on traditional photovoltaic cells or on the most suitable dye sensitized solar cells. An experimental measurement setup employing a microprocessor-based instrument has been created and a set of measures have been carried out. The measures prove that the shading effect at different irradiation angles do not affect significantly the lighting over the PV cell.

In this article is presented the preliminary evaluation of the performance of radiation transmission of glass block, used in support of photovoltaic cells, investigating different internal surface points of the block, which are subject to different shading during daylight hours. The aim is to establish how the edging setting, the only opaque element, can reduce the amount of light radiation during the day, introducing in this way a reduction of efficiency of the entire generation system. The generation system can be based on traditional photovoltaic cells or on the most suitable dye sensitized solar cells. An experimental measurement setup employing a microprocessor-based instrument has been created and a set of measures have been carried out. The measures prove that the shading effect at different irradiation angles do not affect significantly the lighting over the PV cell.

The performance and behavior of five unglazed solar collector installations, devoted to the heating of five outdoor swimming pools located in Switzerland, is studied on the basis of experimental data collected in 1988. Due to the low temperatures involved, hourly efficiencies often exceed 80%. The mean daily collector efficiency is of the order of 60% in optimal conditions and is in good agreement with the G3 simulation program.

The performance and behavior of five unglazed solar collector installations, devoted to the heating of five outdoor swimming pools located in Switzerland, is studied on the basis of experimental data collected in 1988. Due to the low temperatures involved, hourly efficiencies often exceed 80%. The mean daily collector efficiency is of the order of 60% in optimal conditions and is in good agreement with the G3 simulation program.

Domestic heating represents the most dominant energy function in Dutch households nowadays. Using district heat from CHP (combined heat and power) by means of a NGCC (natural gas-fired combined cycle) plants is generally acknowledged as an effective option to reduce primary energy consumption for heating. However, methods to calculate energy savings from CHP differ widely. This paper compares a number of different methods, including the method from the EU CHP Directive, to estimate primary energy savings in comparison with the typically used domestic gas-fired condensing boiler. Real hourly CHP plant performance data is used. An estimation of the CO2 mitigation cost of delivering district heat to Dutch dwellings is made. We find that supplying dwellings with district heat from an NGCC-CHP saves energy, regardless of the calculation method and for a rather wide range of reference efficiencies. CO2 mitigation costs are acceptable from a social perspective (at discount rates up to 4%, excluding fuel taxes) and negative from a private perspective (at discount rates up to 10%, including fuel taxes).

Domestic heating represents the most dominant energy function in Dutch households nowadays. Using district heat from CHP (combined heat and power) by means of a NGCC (natural gas-fired combined cycle) plants is generally acknowledged as an effective option to reduce primary energy consumption for heating. However, methods to calculate energy savings from CHP differ widely. This paper compares a number of different methods, including the method from the EU CHP Directive, to estimate primary energy savings in comparison with the typically used domestic gas-fired condensing boiler. Real hourly CHP plant performance data is used. An estimation of the CO2 mitigation cost of delivering district heat to Dutch dwellings is made. We find that supplying dwellings with district heat from an NGCC-CHP saves energy, regardless of the calculation method and for a rather wide range of reference efficiencies. CO2 mitigation costs are acceptable from a social perspective (at discount rates up to 4%, excluding fuel taxes) and negative from a private perspective (at discount rates up to 10%, including fuel taxes).

Abstract In the Swiss canton of Geneva, an energy efficiency portfolio has been operated since 2009. In contrast, such programs have been in place for more than 40 years in the US. There are numerous lessons to be learnt from their experience. We have therefore conducted a comparative analysis including Geneva and 11 leading states in the US, with the objective to identify explanatory factors for the success of energy efficiency programs. First, we compared total investment in energy efficiency programs between 2006 and 2015 and public policies related to energy efficiency in each state. Second, we analyzed the levelized cost of saved energy (LCSE) of the programs from the perspective of program administrators. Our cost-effectiveness analysis showed that the program investment scale has been strongly influenced by i) the existence of public mandates, which require program administrators to set ambitious targets and maximize their investment in cost-effective energy efficiency measures, ii) financial instruments that ensure program expenditure to be recovered, and iii) complementary funding from other programs. Moreover, learning and accumulated experience of the program administrators allow to reduce the LCSE. We conclude that the combination of financial instruments with public mandates can ensure a high level of effectiveness.

Abstract In the Swiss canton of Geneva, an energy efficiency portfolio has been operated since 2009. In contrast, such programs have been in place for more than 40 years in the US. There are numerous lessons to be learnt from their experience. We have therefore conducted a comparative analysis including Geneva and 11 leading states in the US, with the objective to identify explanatory factors for the success of energy efficiency programs. First, we compared total investment in energy efficiency programs between 2006 and 2015 and public policies related to energy efficiency in each state. Second, we analyzed the levelized cost of saved energy (LCSE) of the programs from the perspective of program administrators. Our cost-effectiveness analysis showed that the program investment scale has been strongly influenced by i) the existence of public mandates, which require program administrators to set ambitious targets and maximize their investment in cost-effective energy efficiency measures, ii) financial instruments that ensure program expenditure to be recovered, and iii) complementary funding from other programs. Moreover, learning and accumulated experience of the program administrators allow to reduce the LCSE. We conclude that the combination of financial instruments with public mandates can ensure a high level of effectiveness.

Abstract In its 2016 Heating and Cooling Strategy, the European Commission (EC) highlighted the strategic importance of heating demand for the energy demand reduction, and further noted that District Heat Networks (DHN) can play an important role in decarbonising this sector. This study applied a thermal atlas approach to map the potential for district heat networks in Switzerland. It extended existing methods with a novel approach to estimating linear thermal demand density in DHN at a national scale. DHN potential for current-generation high temperature networks as well as cutting-edge low temperature networks were compared for current building space heating and hot water demand as well as for two demand reduction scenarios. The method was tested by comparing its results to those of a local engineering study conducted for a Swiss municipality (Brig-Glis). The potential percentage of demand supplied by high temperature DHN was shown to decrease from 66% to 41% with energy saving while the potential for low temperature systems increased significantly from 2.1% to 42%. The percentage of heat demand covered by heat networks decreases less than the percentage of buildings covered, reflecting the strength of heat networks for supplying large fractions of thermal demand in geographically confined areas.