CHP - Combined Heat & Power

The technology involved in CHP has been around for many years although the widescale industrial uptake of it has been relatively slow, however, in recent years its implementation has been more common due to high energy costs. Advantages of CHP include:

- The simultaneous production of useful thermal and electrical energy in CHP systems lead to increased fuel efficiency.

- CHP units can be strategically located at the point of energy use. Such onsite generation avoids the transmission and distribution losses associated with electricity purchased via the grid from central stations.

- CHP is versatile and can be coupled with existing and planned technologies for many different applications in the industrial, commercial, and residential sectors.

Air Technology - CHP

The figure shows the advantage of CHP in efficiency terms over having seperate energy streams. The integrated nature of the CHP process has fewer losses and is therefore more efficient.

The introduction of microCHP and small scale waste-to-energy plants would be an excelletn source of renewable energy in the form of electricity and heat for space/water heating.

We have undertaken a number of feasibility studies looking at CHP in industrial facilities of various sizes under the auspices of the Carbon Trust one of which is outlined below.

 
 

Case Study - Combined Heat & Power (CHP)

This company is a multi-national chemical and pharmaceutical business who has an aspiration to deliver a reduced energy cost base whilst reducing their carbon footprint as part of business plan and Corporate Social Responsibility (CSR) objectives. In addition the site has historically experienced unplanned power outages from grid supply resulting in a significant loss of sales; taking this into account the study has also reviewed security of supply as part of potential CHP business need objectives.

Two implementation options have been identified as part of the CHP feasibility study; they are shown below:

Option 1 to utilise a bio-diesel fuelled CHP installation
Option 2 to implement a natural gas fired Spark Ignition Reciprocating engine CHP with heat recovery steam boiler for process distribution.

Both options identified are based on a ~1 MW electrical and ~1.3 MW thermal installation as calculated from average current and future predicted process steam demand at the site.

At the higher level at present only Option 2 would be economically viable as a potential CHP installation technology, which if implemented could deliver a simple payback of ~5.55 years. Alternatively it is estimated that a Third Party Design, Build, Finance and Operate CHP contract would cost ~£84/MWh including gas fuel costs, however at present calculations indicate a net increase in annual costs for the site of ~£75K a year. It should be recognised however that this is an estimated figure and further commercial competitive tender evaluation is recommended.

In summary, overall saving opportunity identified of £149,498 is the product of grid supplied electricity and Climate Change Levy cost avoidance, plus thermal cost avoidance minus gas consumption cost for CHP and maintenance cost for CHP.