Slightly off topic - Pump question

[Pford75]

The legal wheels continue to turn in relation to the collapse of my wall.

I won't bore you with all the details, but we are in the process of drawing up a costs estimate. As a result of developers blocking some drainage, we installed a permanent pumping arrangement in our cellar (which should drain from a sump, across the road into a ditch which has now been filled).

My solicitors are asking me for an estimate cost for running the pump, but I have no idea how to calculate this. The pump is running apx quarter of the time (ie. on for 10 seconds, off for 30 seconds). Any thoughts/suggestions on how I might come up with a figure for the cost of the electricity? I don't have any power consumption info for the pump (which is a fairly heavy duty one)

 

[Pford75]

I've been doing some scanning online and have come up with the following logic. Welcome any critiques of this:

Similar pumps (based on throughput and cost) seem to consume apx 1-2Kw. A Kw/Hr alledgedly costs 10p

1 x 24 x 365 x .10 = £876 based on 1Kw consumption
2 x 24 x 365 x .10 = £1752 based on 2Kw consumption

Obviously, this is based on the pumps running 24/7, so pro-rating these would give a cost of between £219-£438 per year.

Does this sound logical?

 

[Jon Maine]

You can buy energy meters which clip around the cable and you could monitor it for a week or two to gain an average, you can also buy ex electricity board meters on ebay for around a fiver which you simply wire in both the live and neutral.

It has been drier the last few weeks here so maybe your pump is not working so hard at the moment?

Alternatively just do some calculations on the upper side of the equation present them very tidily to the lawyers, they may just be accepted. If not you have a bit of room to do some horse trading with them should they try to contradict you. But my feeling is if you allow for the worst it would be difficult for them to contradict you if your sums look right.

 

[Flyfisher]

I'm surprised the pump doesn't have a 'rating plate' on it somehwere; is it particularly old? Any possibility of getting the consumption info from the manufacturer?

Something like this would allow you measure the pump consumption.

But I tend to agree with Jon about making some worst case estimates. As long as you can show a reasonable method I doubt anyone would argue too much. And if they do then you could suggest they pay to have an energy meter installed.

 

[Penners]

Sorry if this is obvious, but don't forget to include a costing for repair, maintenance and depreciation of the pump.