Reduction of final electricity and/or fossil energy consumption.
Increases the share of renewable energy sources in the energy mix.
Likely to increase energy independence and energy security.
If electric heat is used as a back-up for low solar periods (winter), then it can increase, the seasonal supply-demand gap (excess generation in summer and generation shortage in winter).
Very likely to reduce global CO2 emissions.
Likely to avoid emissions of harmful pollutants, especially in urban areas (heating oil-boilers can remain off in summer).
Minimal environmental impacts due to waste (non-toxic, largely recyclable materials).
Likely to have limited impact on the cost of the energy transition, unless prices of the fuels replaced by solar thermal rise sharply.
May improve balance of payments by substituting oil and/or electricity imports.
Reduce Confederation income from the tax on mineral oil and electricity under the current taxation system.
Decentralised solar thermal systems use solar collectors to harvest solar energy for use in the form of heat. They employ typically roof-mounted rectangular collectors made up of flat plates or evacuated tubes which capture solar radiation and thus generate heat.
The produced heat is then transferred to a water-filled thermal store and used to supply hot water and space heating energy. The thermal store can release heat for a period of hours up to several weeks, depending on the size of the tank, insulation and usage patterns.
• Decentralised Solar Thermal competes for roof-top area with Photovoltaics (PV). PV is often a more attractive investment due to guaranteed feed-in tariffs, whereas profitability of solar thermal hinges on prices of the conventional energy source that is being displaced.
• Unlikely to completely replace the need for a conventional water heater, so can be perceived as an additional capital cost and source of complexity, rather than as a means to save money.
• The produced heat cannot be stored for long or transported to another location, therefore much of the summer generation is wasted.
Next tables contain the assumptions that have been introduced in the Photovoltaic energy model of the calculator.
*Based radiation data for the village of Verbier.
|CO2-eq. emissions [kgCO2-eq./GWhth]||10'973|
|Deposited waste [UBP/GWhth]||1'718'064|
|Specific investment [CHF/kWth]||2'090|