Direct Generation/Combined Heat & Power Systems
Let me explain the differences and similarities between the two. A generator is just a straight up generator and a Combined Heat & Power System is a generator with a heat and exhaust engine jacket attached to it. Thus there is one price for a straight up generator and another for the heat/engine exhaust jacket package. The generator provides the electrical output and the heat/engine jacket provides for the thermal load. Thus one has the value of the hydro produced by the generator+ the value of the heat produced by the exhaust and engine jacket. A CH & Power system is the optimal solution if you can effectively use the thermal load. In some cases due to the physical outlay of a building or the manufacturing process you can’t. Generally, in Ontario, the cost of producing electricity via a generator is approx 10 cents per kWh hour. The value of the heat produced by the exhaust/engine jacket is approx 2.5 cents per kWh if you can use the entire thermal load. Thus, the net cost would be 10-2.5 or 7.5 cents per kWh. (Even if you can’t use the entire thermal load you can compare the additional cost of the exhaust and engine jacket to the value of the heat produced to see if it’s worth adding the exhaust and engine jacket to any system).
As I have mentioned on this website the cost of hydro in Ontario for many typical medium to large sized business is approx. 18 to 22 cents per kWh. Again, the cost to run generator which would include, fuel, maintenance and operational costs and capital replacement is again approx 10 cents per kWh. Thus, the saving is quite substantial. A generator can last up to 60,000 before an overhaul and can be used in parallel etc. They offer quite a bit of flexibility. With respect to a CH &B P system, if you can reach a 65% efficiency factor in Ontario you may qualify for a 40% capital cost grant for your project.
A CH & Power System can have a combined efficiency of over 85%
-40% from the electrical efficiency of the generator
-45% from the thermal value (heat recovery).
If you have ever been on a cruise ship then you have seen the generator in action. The power provided to propel the ship and lights and all electrical outputs has/was generated from a diesel generator. The diesel generator converts the mechanical energy to electricity. It’s exactly the same principle as the steam engine which ushered in the Industrial Revolution. It’s a proven technology which has come back into favour due to the high cost of hydro in Ontario. It’s a basic combination of the laws of physics, the electrical efficiency of a generator/CH & Power system that are at play. Moreover, it has the added benefit of providing for backup power and the creation of an off-grid system with another new technology of energy management storage systems (i.e. batteries).