Electric Generators

[Brian]

Can anyone offer any assistance on this particular query?

We are moving our woodwork shop from its current (free) site in the next few weeks. We need some volts there, - what do you know about generators? Or do you know a man who does know?

We need about 2kva and it needs to be reasonably quiet (fussy neighbours). Also, it needs to run for 7-8 hours without re-fuelling. Budget, I guess is up to £500.

[willk]

2kva? That won't run a kettle! Do you mean 20?

Mine is 200kva - runs all kindsa stuff. What do you need to run over what operating period. How long does this thing have to last for?

[Brian]

Hi Willk,

I'm a complete dodo at this kind of stuff.
You may have gathered that I am enquiring on behalf of a friend (whom I hope is silently reading your erudite reply!).

I gave up "doing" anything usefull years ago!

[jimn]

200 KVA is pretty huge for domestic use, I guess they would cost upwards of 20 grand.

What sort of equipment will you be powering? An inductive load will require a higher KVA than a resistive load.

The run time will be dependent on the tank size, do you have a prefrence on fuel and do you need electric start?

Here is a 5.9KVA (about 4800 watts) Diesel with electric start and an internal 21 litre internal tank
It is between £2.2000 and £2.5000 depending on options

http://www.justgenerators.co.uk/pages/Pramac_P6000S.htm

[willk]

Originally Posted by Brian

I gave up "doing" anything usefull years ago!

Oh I don't know, you were quite useful when we met last year

The post did puzzle me. A 2kva (2000va) genny is the sort market traders use and much less than your budget.

A woodshop will probably require 20kva or more and possibly 3 Phase supply. A silent genny in this range is also in another price range entirely. If it is for long term use (as this would be) you should consider a 1500rpm "Continuous cycle" unit (less stress, less maintenance, longer life) 3000rpm "Standby" units tend to be cheaper but not designed for this application. Continuous units tend to have larger tanks or remote connections for a fuel line.

Something temporary to run tools during renovation and install might be what you want? If so, you'd probably get away with 4-5kva depending. Any decent brand should do but silencing needs a housing and extra cost.

My set is in a sound proof shed (useful for other things too ). She can supply a small village at 200kva (3 phase) which is 180Kw approx and run for 16 hours at full chat. Plant is a straight 6 turbocharged Volvo 120AG, auto start and changeover. If you want, I'd swap for your RIB and just buy a few candles instead

[Brian]

Received the following reply from my earlier e-mail to my pal who is enquiring:

" I'm planning to charge a small storage radiator to keep the workshop frost free, that's 900W. Then lights & radio etc, say 200W, and power tool, say another 200W. Add a bit for contingency and you have continuous probably 1500W. Sounds (from Tony) that we need 2000kva plus then. When we've got a cold night forecast, the storage rad will need about 7 hours to charge, so it could run for that time each day in winter. "

BTW I have absolutely no idea who Tony is.
Er, does this help?

[doggypaddle]

Power tool 200W? are you sure? my angle grinder is 2Kw, drill is 900w and smaller drill is 600w. The Honda 26i inverter generator will run the grinder OK, but the start up power is more like 4kva and makes it grunt a bit,
the old non inverter 3kva genny just shuts down on overload before the grinder gets up to speed..
I would say you really should be looking for something a bit bigger so its not flat out all the time too.

[Mollers]

A ran a small complex of workshops via a genny a few years ago. It was a huge PITA. A bit of EU money halved the epic mains install bill and the genny went.
I started off with a 15kva Lombardini set which did surprisingly well.
I reckon 10-15kva would do you. Forget anything other than diesel, get a 800ltr gas oil (red diesel) tank and make it very, very secure. Mine lives in a steel shipping container.

[willk]

Originally Posted by Brian

Er, does this help?

Ah, OK - that's a bit different then

If he really knows what the "power tool" uses and he keeps the lighting economical then something like this might suit.

It runs all day on a fill and is 70 decibels - similar to a quietish hoover. You can work wonders to reduce noise by careful siting and some sound absorbing materials. It's close to budget too (IOM VAT???). I have NO IDEA if the brand is any good but the engine is Honda.

I'd have serious concerns about the longevity under those running times, it's big hours but I guess there should be years in it, TBH. Keep the oils changed etc.

_____________________
EDIT: Mollers is right (but Brian's mate doesn't have the budget for it...)

[Mollers]

Originally Posted by willk

Ah, OK - that's a bit different then

If he really knows what the "power tool" uses and he keeps the lighting economical then something like this might suit.

With the rad pulling 900w and a light on, the start-up on a 800w planer would stall that baby.

We've worked off site with a 2.7kva Honda/Stephill set. You can't run much off of it, a kettle has it grunting.

Also, with continuous running, you can pour a good few quids worth of liquid gold through these things in a week.

[willk]

I think we may be dealing with a Gentleman Woodturner here - no table saws!

I agree though, gennys are like boat engines, you can't have 'em big enough. When I bought me Genny, I was pulling 120 kva max, that's tipping 180 now at peak. I've been dodging increased load but one more big piece of kit and I'm into a serious upgrade. Trouble is, the roof might have to come off the shed

[Downhilldai]

Originally Posted by willk

When I bought me Genny, I was pulling 120 kva max, that's tipping 180 now at peak.

You weren't posting on ribnet when you bought it.

[Mollers]

Originally Posted by willk

I think we may be dealing with a Gentleman Woodturner here -

Best not shove the chesil in too hard.

[BogMonster]

Having grown up on a farm where we generate our own power I can vouch for the fact it is

noisy
expensive
a total PITA

Everybody here uses 1500rpm air cooled Listers in that role (typically 8h/day 365 days a year) as they last forever - our last TS3 had 30,000 hours on it when it was replaced and the hone marks were still in the bores when it was stripped for a complete rebuild plus you can still get spares for anything though if you keep it in a dry shed with proper ventilation and change the oil every 250 hours all you really need is filters and the odd AVR and then chuck the whole thing away every 10-12 years and spend £6k on a new one. Downside is they are bloody noisy, stick your head under the bonnet of a Tdi engined Land Rover and rev it a bit and that's pretty close. People here have tried all sorts of other stuff over the years, but nothing else comes close. There are 3 models in the current TR (formerly TS) range, 1, 2 and 3 cylinder which produce about 4.5, 9 and 13KW in current spec I think (haven't double checked that) and you can have 1ph or 3ph, 1500rpm 50hz or 1800rpm 60hz.

I have an air cooled single cylinder 3000rpm Hyundai badged diesel 'made in China' job at my house on the farm - OK for the money but won't last long but with no more than 100 hours a year it will do me for ages. It probably won't outlast the Lister 6/1 in our shearing shed which was installed in 1958 though...

There seems to be a lot of uncertainty on what is required - a big difference in cost, installation and everything else between 2kw and 200kw!

The cost of running a generator 7 hours a day will kill him - when I used to look after the generators our TS3 (about 12KW though running at only part load for a lot of the time) used about 800L of diesel a month IIRC. I hate to think what willk's diesel bill is (and wonder exactly what he needs 180kw for!)

No idea what the circumstances are but it would probably be cheaper to find a more expensive to rent workshop with some wires into it?

[willk]

Lister indeed, Bogmonster. My first thought in this guy's case but the silencing would have doubled the bill. I sourced a secondhand Lister/Petter 10KVa set for my father for around £1000. He has it in a shed and it runs the whole house for him, but you KNOW when it's running. Everyone nearby does! It's as old as the hills but still starts on the button and generates with narry a flicker.

Originally Posted by BogMonster

I hate to think what willk's diesel bill is (and wonder exactly what he needs 180kw for!)

About 250L/day. More when Genny is sucking up 25-30L/Hr, luckily she's only Standy.


As for the 200KVa..., well, building a Clone Army takes a lot of ffiiizzzzziiiip!

[Pikey Dave]

I recently replaced my 2.2 Honda/Stephill for a 3.7kva of the same pedigree. The new one cost £399 +VAT, the old one served me well for 10yrs site work. As previously mentioned, careful siting works wonders with noise. Running that all night just to charge a storage heater sounds a bit extravagant, I'd consider a portable LPG heater or similar.

[Brian]

OK everyone. I think we have got it now. My friend tells me he has all the info he needs.

Thanks very much to everyone who replied to this thread.