Am i dreaming?

[Dave Payne]

I know this is possible, but is it realistic?

 

Coffee roaster on the boat, it pulls max 3300 watts at full power for about 15 minutes, then about 300 watts for 3 minutes, this is the time per roast of 1kg beans.

 

Now if i was to fit this on the boat and run from batteries, i would need a hefty invertor and bank, or just run it from a genny, but then is a genny that supplies 4kw too much?

 

 

 

 

[ditchcrawler]

I know this is possible, but is it realistic?

 

Coffee roaster on the boat, it pulls max 3300 watts at full power for about 15 minutes, then about 300 watts for 3 minutes, this is the time per roast of 1kg beans.

 

Now if i was to fit this on the boat and run from batteries, i would need a hefty invertor and bank, or just run it from a genny, but then is a genny that supplies 4kw too much?

 

 

 

 

Are you sure on that first figure as there are not many plug in appliances other than welders that draw over 3Kw

Yes the genny would handle it OK

Edited January 19, 2016 by ditchcrawler

[Delta9]

3300 watts is a hell of a lot for a coffee roaster, is it a commercial one?

[Dave Payne]

Yep, had a power monitor thing on it at the house, would pull between 3200 watts and 3300 watts during the roast. I made sure i had good qulity artic cable and plugs, and monitred them for heat.

 

No issues in the 6 months i used it, and i know of another user with the same roaster running this set up for over two years.

 

In terms of batteries though, what size bank would i be best to look at if i was running the roaster for say 6 hours a day?

3300 watts is a hell of a lot for a coffee roaster, is it a commercial one?

 

 

Semi, its a 1kg roaster.

[DHutch]

You can run anything you like, if you have enough to run it.

 

3300w is absolutely top-whack for a 13amp plug (13*240=3120w) but I expect it will take it for 15 minutes before the plug-top fuse heats the live pin up enough to be an issue. If its light-commercial I expect it was designed for a 16amp cee-form like we use for shorelines.

 

#

 

Obviously a 4kva generator should run it, assuming its basically a resistive load (heating element) 3.3kW = 3.3kVA , things like microwaves have a high 'power factor' and may draw 3.3kW but 5-6kVA but I expect this in unlikely. A similar sized inverter will work equally well, assuming you have the battery power available and a means to put it back in.

 

 

In terms of having battery capacity; 3300W at 12v volts is 275A so for 15minutes that's around 70Ah or alternatively 3300W for 15 mins is 826Whours

 

If you have three 110Ah batteries that's 330Ah total, and as you can factor in using half of that without knackering the batteries, 165Ah

An inverter should be around 90% efficient, so 70/0.9=78 which means if you draw that out if you draw of you available 165 you have used half the capacity of the batteries.

 

If you have a 90amp alternator on the engine, and have that running at the same time, that will be put a third of the power back in directly as your doing it. So you will only use 1/3 of the battery banks capacity.

 

 

Obviously however you will then need to pull all of the power back in in to the batteries and while the load is there you will get the full 90amps from the alternator, as you will for a while in the 'bulk charge' period, as the load goes and the battery voltage comes up, the rate the batteries will accept charge will tail off, so to get back to about where you are might take several hours of running the engine.

 

#

 

So in short, if you have a suitable generator or landline its easy, and if you have a suitable inverter it should be ok as long as you run the engine while doing it and or have another good option for putting the power in.

 

If you are moving often, set it running in the morning just as you set off, and after eight hours boating come the evening you should be about back to rights. This assumes its largely at a 'for personal consumption' and your not planning on roasting coffee continuously all day every day!

 

If you are specing a new boat another point worth mentioning is that, a lot of inverters-charger combis have a 'source mixing' option so if you have some main but not the full 3.3kW you can set it to take the maximum power it can from the 'mains' and then add to it its own rated capacity. Say if you have a smaller generator (say a 1 or 2kva honda suitcase) or a limited shoreline (some are only fused at say 6amp or just under 1.5kW) .

Bit of a wall of text, and a few numbers, but hopefully that makes some sort of sense and may gives you enough to play with the numbers yourself? A larger battery bank will take more drain, but need more charging afterwards, a larger alternator will increase the bulk-charge rate but have limited effect on the length of the tail at the batteries become more charged. Etc.

Daniel

[Paul C]

Yep, had a power monitor thing on it at the house, would pull between 3200 watts and 3300 watts during the roast. I made sure i had good qulity artic cable and plugs, and monitred them for heat.

 

No issues in the 6 months i used it, and i know of another user with the same roaster running this set up for over two years.

 

In terms of batteries though, what size bank would i be best to look at if i was running the roaster for say 6 hours a day?

 

 

Semi, its a 1kg roaster.

 

Does it have a BS1363 plug (ie normal domestic one) or an industrial one (can't remember the technical name)? If the latter, then at 3300W I'd say you can't simply cut it off and fit a domestic plug, but you'd need to have the industrial plug and corresponding socket/outlet installed on the boat too. Obviously you'd need the wiring to be of an appropriate spec but its just a case of ensuring this is correct, and is perfectly DIYable. My concern would be that you'd need a good battery recharging regime and also you'd get one "shot" of it from full batteries, more or less, so you may be somewhat limited in the opportunity to run it. Or alternatively, size the battery bank so it can cope with more usage, or other loads too (which I suspect, we're into 5+ 110Ah batteries or something like T105s or traction batteries). Don't underestimate the underlying cost of upgrading the inverter, sockets, wiring, charger, battery bank, 12V cabling, etc etc.

 

I don't think you'd find a marina it could run at - while in theory the connector for a shoreline is 16A capable, in practice they assume something like 5A max per boat and you may find it trips out too frequently, and annoys all the other boaters in the area, to be useful.

[Dave Payne]

My head hurts!

 

I think a genny is the best option, decent one that will run with no problems....

[Delta9]

Would it not be easier to purchase a smaller coffee roaster, or are you planning to roast coffee as a commercial venture?

[Dave Payne]

 

Does it have a BS1363 plug (ie normal domestic one) or an industrial one (can't remember the technical name)? If the latter, then at 3300W I'd say you can't simply cut it off and fit a domestic plug, but you'd need to have the industrial plug and corresponding socket/outlet installed on the boat too. Obviously you'd need the wiring to be of an appropriate spec but its just a case of ensuring this is correct, and is perfectly DIYable. My concern would be that you'd need a good battery recharging regime and also you'd get one "shot" of it from full batteries, more or less, so you may be somewhat limited in the opportunity to run it. Or alternatively, size the battery bank so it can cope with more usage, or other loads too (which I suspect, we're into 5+ 110Ah batteries or something like T105s or traction batteries). Don't underestimate the underlying cost of upgrading the inverter, sockets, wiring, charger, battery bank, 12V cabling, etc etc.

 

I don't think you'd find a marina it could run at - while in theory the connector for a shoreline is 16A capable, in practice they assume something like 5A max per boat and you may find it trips out too frequently, and annoys all the other boaters in the area, to be useful.

 

 

I run at present the following in my marina, in fact did it this morning,

 

Rocket espresso machine, 1600 watts

Coffee grinder, 850 watts

Electric heaters x 2, 2000 watts

 

Not sure if the espresso machine was pulling the full 1600 watts at the point i put the heaters on though, it mainly pulls this over the first few minutes when heating the boilers up.

 

 

Have also had my little roaster running at 1300 watts with both electric heaters on.

 

So i know the shore line is a good one!

 

 

 

The big roaster came with a 240, 13 amp plug fitted.

Would it not be easier to purchase a smaller coffee roaster, or are you planning to roast coffee as a commercial venture?

 

 

Already have one, but the aim is to CC in 2017 and roast sell/beans from boat, markets and online and for that i would need the 1kg roaster, the little one only does 250g per roast.

[nb Innisfree]

Running for 6 hours assuming no thermostatic control you would using in the region of 450-500 ah @12v, that would require a big inverter and battery bank. Halving that due to thermostats still requires the same size inverter and a big batt bank. Running directly from an inverter genny ticking over when off load would be better.

Edited January 19, 2016 by nb Innisfree

[Dave Payne]

Something like this running the roaster only then?

 

http://www.screwfix.com/p/sdmo-perform-4500-gaz-tb-uk-3900w-generator-230-110v/81123#product_additional_details_container

[bottle]

No, no , no you will go deaf with that running.

[Dave Payne]

How about if i put it away from the boat on a long cable, near other boats!

 

Ok, so just kidding, so do they make nice powerful, quite gennys?

[Dave Payne]

This?

 

http://www.generatorsnextday.com/hyundai-hy3600sei-leisure-inverter-generator-with-electric-start--3400-watt-388-p.asp

[bottle]

That should be quieter, did not check the dB (decibels) which obviously the manufacturers will quote the best figures.

I believe there are different ways of measuring it

 

This needs to be checked:

 

3400 Rated Watts. is that continuous or peak?

 

In the blurb it says, maximum of 3400w of power but for how long? same question.

[Dave Payne]

It says running time, upto 12 hours.

 

And 58dbs @ 7M

 

 

The things to jump to my mind are, a jenny is cheaper to run than an engine in terms of fuel and servicing?

 

If the genny fails then its only £1k to replace, engine would be a fair bit more i guess?

 

 

 

I was thinking of picking up a new 20ft sail away for about £6k and using this for the roasting side of things, so could think about building a cabin for the genny that was fire proof in case of things going boom!

 

 

Lots of food for thought this year, and saving the pennies to support me for the year after to give it every chance.

[bottle]

Here you go if you want the ultimate:

 

http://power.cummins.com/content/marine-qd-50-hz-4-kw

 

This one is, 68dB @ 1m

[Graham.m]

 

 

I run at present the following in my marina, in fact did it this morning,

 

Rocket espresso machine, 1600 watts

Coffee grinder, 850 watts

Electric heaters x 2, 2000 watts

 

Not sure if the espresso machine was pulling the full 1600 watts at the point i put the heaters on though, it mainly pulls this over the first few minutes when heating the boilers up.

 

 

Have also had my little roaster running at 1300 watts with both electric heaters on.

 

So i know the shore line is a good one!

 

 

 

The big roaster came with a 240, 13 amp plug fitted.

 

 

Already have one, but the aim is to CC in 2017 and roast sell/beans from boat, markets and online and for that i would need the 1kg roaster, the little one only does 250g per roast.

 

May I suggest that while the roaster is 3000kW heater and 300W motor if you want to run anything else a the sametime, the expresso machine for samples maybe looking at a 5kVA+ generator might be a good idea it should give you about 4.5kW

[cuthound]

It says running time, upto 12 hours.

 

And 58dbs @ 7M

 

 

The things to jump to my mind are, a jenny is cheaper to run than an engine in terms of fuel and servicing?

 

If the genny fails then its only £1k to replace, engine would be a fair bit more i guess?

 

 

 

I was thinking of picking up a new 20ft sail away for about £6k and using this for the roasting side of things, so could think about building a cabin for the genny that was fire proof in case of things going boom!

 

 

Lots of food for thought this year, and saving the pennies to support me for the year after to give it every chance.

I used to specify commercial standby generstor indtallations for clients. If you don't want to upset anybody or go deaf get one rated at 70dB(A) or less at 1 metre.

[FadeToScarlet]

Powerful, quiet, cheap.

 

Pick 2 options.

[Graham.m]

Or even 50dB(A) at 1 metre if your going to go to shows etc

 

[ditchcrawler]

If you plan to mount it in a butty make sure you don't restrict the cooling air flow to it by trying to improve the sound insulation ,

[Alan de Enfield]

If doing it commercially then go the 'whole hog' and use a proper, quiet water cooled marine generator.

 

You are looking at around £6000 for the generator and £1000 for the installation / exhaust kit.

[Graham.m]

If doing it commercially then go the 'whole hog' and use a proper, quiet water cooled marine generator.

 

You are looking at around £6000 for the generator and £1000 for the installation / exhaust kit.

 

and with gas/water separator they can be almost silent. I know of some that are inaudible 30 feet away

[Delta9]

or get a wood burning coffee roaster. With the added bonus that you can now charge more for your coffee cos 'wood roasted coffee' sounds fancy.