ECN Forum Forums General Topics of the Trade General Discussion Area Wireless sub-meters

Interesting topic with running the diesels.

I'm aware of it being done in the Netherlands by the bigger hospitals to keep the peak demand down between 17.00 hrs and 19.00 hrs. without cutting of electrical services.

It is done here in NZ by the railways, that it is sometimes cheaper to run a diesel, dragging 2 "dead" electrics + train behind it than using the Grid supply at certain peak periods during the day.

The charges per ½ hour can be up to 50 cts / kWh at certain TOU periods.

For non-critical metering (not disturbance or harmonic), emon dmon has a good product that have clamp-on CT's that do not require the disconnect of the power conductor to install.

For peak shaving, if you consider that a plant that pays demand charges for an entire month or series of months based on the highest 15-minute rolling demand reading made by the meter, then you try anything you can not to have a peak recorded. I had a client that had metering charges that would ratchet up each recorded increase in demand, and the highest demand would be billed for the entire year. The cost of diesel or natural gas is generally much cheaper than demand penalties.