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Is micro CHP worth the money?

Try this simple calculation by entering your details in the boxes, to work out how much you can save.

Many people interested in micro CHP are unsure whether it is economically worthwhile to install such a system.  This simple calculator is intended as a tool for you to calculate your potential energy savings, based on your current fuel bills.  From this you can work out how long it will take to pay back the investment in micro CHP.

Please note that this spreadsheet is provided only for you to undertake an estimate and that each home and household is different.  You should satisfy yourself that the result is reasonable.

An example of a simple calculation is shown below for illustration only.  It assumes that the system is installed in parallel with the existing power supply and that surplus generation is exported to the grid and any shortfall in requirements is imported from the grid.

Example

WhisperTech (0.8kWe/6kWt) micro CHP unit in an average sized family home with annual heat demand of 18,000 kWh

Annual heat demand 18,000 kWh
Running hours 3,000 hours
Electricity generated 2,400 kWh
Own use of generation 85 %
Unit cost of avoided import 6.5 p/kWh
Value of avoided import 133 £
Unit value of export 2.5 p/kWh
Value of export 9  £
Total value of generation 142 £
Marginal cost of unit 500 £
Simple payback 3~4 years

 

Calculator

This calculation assumes that you are considering replacing your boiler (which has reached the end of its useful life) with either a micro CHP unit or a new 80% efficient gas boiler.  It is based on replacing the boiler with a WhisperGen micro CHP unit.  You will need to know your gas and electricity costs for a complete year, which you can see from your annual energy bills.

Clicking on the "calculator" button will take you to a Microsoft Excel spreadsheet.  You need to have MS Excel installed to run this calculation.

 

Contact : info@microchap.info

Disclaimer:  Information is provided for general information only and no endorsement or recommendation of any company or product should be inferred.  This is not a commercial site and none of the companies mentioned are sponsors of the site.  Please note that the views expressed on this site are  entirely my own and are in no way connected with the official position of my current or previous employers.

This page was last updated on 12th February 2008  © Jeremy Harrison