Manufacturers Best Practice Guide

Combined Heat and Power: Tips for Energy Savings

Actions to implement effective cogeneration:

  • Calculate the energy used in your steam generation system. The Excel-based software "easyCOGEN.xls" allows non-experts to carry out a first rough assessment whether the installation of a cogeneration plant is a good option or not. You can download this file at:www.cogen-challenge.org
  • Determine which is the most appropriate cogeneration unit for your needs. If the unit is too small, the opportunity to save more energy is missed. If the unit is too big, energy will be wasted. In most cases a feasibility study is necessary because there is no standard formula to calculate the size of a cogeneration unit (unlike for a typical boiler). For the same enterprise or building, there is a wide range of suitable cogeneration size options, but only one will achieve maximum benefits. The more hours of a year the cogeneration unit is in operation, the more money is saved during this year. Therefore, project developers should choose a size that does not cover the highest possible heat load, but a load that will allow the cogeneration unit to run for at least half the year.
  • Take advantage of state and federal rebates and incentives.
  • Involve your local electricity distribution network operator. In the case of bigger units the impact on the grid needs to be checked and the point of interconnection needs to be defined. It is also helpful to know the interconnection costs. These costs can vary from 5% to 20% of the total installation costs.
  • Add chiller capacity, if appropriate.

Industrial Application of Cogeneration
The most common industries to use CHP are petroleum refining, petrochemical manufacturing and pulp and paper manufacturing. Other less energy-intensive industries are also investing in CHP.

American Council for an Energy Efficient Economy notes that growth in cogeneration capacity can be attributed to four major factors:

  • Technological advances that drive down costs while improving system efficiencies; new technologies have also made it possible to cost-effectively install smaller and more flexible prime movers.
  • Existing boiler inventories are nearing the end of their useful life, and will soon need to be replaced
  • Environmental policies, particularly those directed at reducing GHG emissions, have increased pressure to adopt cleaner, more efficient energy technologies
  • Deregulation of markets that create new opportunities for small-scale distributed generation

CHP is recognized as an important tool for reducing GHG emissions. Indeed, European Union plans attribute 20% of total GHG reductions to the increased deployment of cogeneration. The United Kingdom relies even more heavily on CHP, assuming that as much as 50% of their GHG reductions will stem from its use.