Power Generation
Generators, usually powered by diesel engines, are very widely used either as standby
or mobile power sources. In addition, generators used in distributed power plants
may run on diesel or gas.
Standby generators may only ever be started for periodic testing, nevertheless if
a mains failure does occur they need to be able to operate continuously for as long
as is required without breaching local air quality regulations or causing a nuisance.
In the case of a large generator in an urban environment, this can be quite onerous.
Another consideration is that standby generators can have very long service lives,
which means that a degree of ‘future-proofing’ is often demanded as a planning condition.
The exhaust emissions from mobile generators are also very important in certain
situations, for example at an open air festival a lot of people will be in close
proximity, whilst if a mobile generator is used to provide temporary power in response
to a grid failure it may well spend a considerable time operating in close proximity
to houses. In either of these examples, the environmental impact clearly needs to
be minimised.
Generators used in distributed power plants are likely to be larger and to clock
up far more hours per year than either standby or mobile units, and for these reasons
their exhaust emissions require careful consideration. One increasingly popular
variation on distributed power is combined heat and power, which often receives
grant funding because of its capacity to reduce carbon dioxide emissions. Understandably,
this grant funding usually imposes strict limits on the toxic emissions in order
to prevent them outweighing the benefits of the reduction in carbon dioxide.
(Photo: Catalytic converter for 400 kVa containerised genset)
(Photo: Exhaust systems incorporating diesel particulate filters
for a pair of 400 kVa standby generators)