Talk:Wet stacking

Very poorly written article. The bit about hospitals and generator capacity appears very amateurish.

Obtuse

This article is on a bunny trail. I fixed it nominally, but now I am going to hack into it. This article should discuss a malfunction of a diesel engine, not policies of hospitals. By the time anyone reads this, hopefully it will be back on track. Below are sections I removed and put here for the sake of anyone who might want to put this info in an article on "why hospitals run generators at full load" or something obtuse like that. I like to saw logs! (talk) 06:11, 23 May 2010 (UTC)

In hospitals

Some hospitals purchased large generators when they had the chance, anticipating expansion of their facilities. As a result, some failed to meet the percentage limits. Some of those that don't meet the load requirements have connected load banks to load up the generator to 80% of nameplate for a four-hour annual run.

Load bank use can have unexpected consequences; care must be taken if it is desired to connect an external load bank to a required emergency power system, one must make sure that there is some automatic disconnect included that will take the load bank off-line if the generator is needed by the facility during the load bank run. If not, it is possible to seriously overload the system if the emergency load from the hospital is added to the 80% load of the bank, causing a failure of the system when it is needed most.

The American hospital accreditation body JCAHO has cited numerous hospitals for not running generator sets under at least 30% load as specified by the nameplate, or 50% of the normally connected emergency load, whichever is greater. Many hospitals are installing internal radiator-mounted resistive load banks directly and permanently into the generator enclosures. This on-board load bank then affords the hospital the opportunity to run the generators under load without risk. In addition to preventing wet stacking and functioning as a superb test of available kW, on board load banks can also improve asset life and fuel efficiency.

NFPA 110 speaks to the generator and wet stacking issues, and the 1997 JCAHO environment of care standards also address some change in the thinking on load bank testing.

References

Selling power to the grid

In a number of countries including the UK payment can be received for running generators and feeding into the grid from the grid operator known as National Grid Reserve Service. Whereas running a generator against a load bank incurs a cost, these type of arrangement can incur considerable profit to the operators. In the UK payment can be of the order of $50,000 per annum for about 60 hours per year full load run. Similar deals operate in the USA.

References