Don
What power consumption are you expecting to need to meet?
Jokester
Jokester
Anybody know if you can run inverters in parallel?
- Thread starter SB118
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SB, are you planning on running everything electrical from it, or just reducing your bills?
If the latter then some of the dinky 12V halogen lights might be an option. Plus if you could have a 24V system as well (or instead) there is shedloads of stuff (TVs, fridges, microwaves, kettles) available for HGV drivers.
Just a thought.
If the latter then some of the dinky 12V halogen lights might be an option. Plus if you could have a 24V system as well (or instead) there is shedloads of stuff (TVs, fridges, microwaves, kettles) available for HGV drivers.
Just a thought.
Adam_151 said:
I'm planning on using the exsisting earth curcuit, along with a chuffing great big spike into the back yard. Looking for a CU to put along with the genny, coupled with an RCD. Hoping to completly disconect the mains and feed the current CU from the "shed supply" of either the genny or battery stack.
Jokester said:
I'm planing to cover everything in the flat, the only failing point is the electric shower which has a higher load than the rest of the flat put together
Might have to leave that one running from the mains until i can sort something out.
Mmmmmm, you've got me thinking about down in my garage now. I need power and I've just inherited a spare car battery. I might mock up a system for the lights and radio, then when I need to weld or use the compressor I can run a lead round the corner as normal. How big is that engine of yours, cc and dimensions? What is it, a diesel that will run happily on cooking oil?
Capacity is about 350cc i think, dimensions are, umm, BIG (restored engine of similar type, you can see a dog in the background, bit of scale )
For the amount of arsing around to run a set of lights n shi you'd be better off with a cheapo b&q 850 genny i'd think.
)For the amount of arsing around to run a set of lights n shi you'd be better off with a cheapo b&q 850 genny i'd think.
Associate
Won't work
Well not at that price. There are a couple of problems with your plan so far.
1. inverter is too cheap. Sounds silly but it is. At that price you aren't getting a nice sine wave...you are getting a square wave. Expect your pc, hifi, tv and what not to have a significantly lower lifetime. If any lifetime at all. I blew up a perfectly good clock radio in about 5 minutes off my significantly more expensive inverter (still rubish though).
2. Inverter is too small. 1000 watts at that price will be peak. If you are seriously considering doing this you need to spend AT LEAST £1000 on the inverter. Perhaps more if you intend to use things like a washing machine or even an electric kettle which often take 2kw. Look at people like sterling inverters and mastervolt.
I know this all from living on a narrow boat who get used to being off grid as it were.
I would seriusly consider 12v lighting if you are serious about this. Remember that inverters are about 80% efficient so to run say 10 light bulbs at 100 watts you need 1000watts of ac so 1250watts of dc which at 12v is 104Amps.......JUST for a few light bulbs. Get used to not having the tv/computer/anything on if you need to do any washing.
I know from watching other people trying that you can't get a equivalent to a normal electricity supply using this method. And once you have bought the kit you will probably take ages to recoupe the cost...if ever!
oh and to answer your initial question...yes...if its designed for it. They cost a fortune though. I think £2k.
Sorry to **** on your chips.
Well not at that price. There are a couple of problems with your plan so far.
1. inverter is too cheap. Sounds silly but it is. At that price you aren't getting a nice sine wave...you are getting a square wave. Expect your pc, hifi, tv and what not to have a significantly lower lifetime. If any lifetime at all. I blew up a perfectly good clock radio in about 5 minutes off my significantly more expensive inverter (still rubish though).
2. Inverter is too small. 1000 watts at that price will be peak. If you are seriously considering doing this you need to spend AT LEAST £1000 on the inverter. Perhaps more if you intend to use things like a washing machine or even an electric kettle which often take 2kw. Look at people like sterling inverters and mastervolt.
I know this all from living on a narrow boat who get used to being off grid as it were.
I would seriusly consider 12v lighting if you are serious about this. Remember that inverters are about 80% efficient so to run say 10 light bulbs at 100 watts you need 1000watts of ac so 1250watts of dc which at 12v is 104Amps.......JUST for a few light bulbs. Get used to not having the tv/computer/anything on if you need to do any washing.
I know from watching other people trying that you can't get a equivalent to a normal electricity supply using this method. And once you have bought the kit you will probably take ages to recoupe the cost...if ever!
oh and to answer your initial question...yes...if its designed for it. They cost a fortune though. I think £2k.
Sorry to **** on your chips.
Last edited:
No worries, the inverter outputed stuff was just to run overnight (fridge, etc), the main generator output would be used during the day. Nice to get somebody who has done similar stuff into the fray 
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you cannot run inverters in parallel because you have no means od detecting phase angle or adjusting it for that matter, to run in parallel the phase sine waves must be exactly in step with each other. the voltages must also match, and you must have the load/voltage droop the same
BTW the same applies to altenators unless you cane detect the phase angle ( using at the most basic a syncroscope ) and a means of adjusting the speed relative to each other you would not be able to.
transformers can be used in parallel if they are designed to do so , evan then a large recirculating current may be set up
its a complex subject not a thing you can play with without the proper test gear
As dingleberry states they are to cheap they will have a very poor output wave form no way will it be a sine wave
BTW the same applies to altenators unless you cane detect the phase angle ( using at the most basic a syncroscope ) and a means of adjusting the speed relative to each other you would not be able to.
transformers can be used in parallel if they are designed to do so , evan then a large recirculating current may be set up
its a complex subject not a thing you can play with without the proper test gear
As dingleberry states they are to cheap they will have a very poor output wave form no way will it be a sine wave
Associate
Might work then. I take it the genny has 240v out then?
Bear in mind you need a good battery charger (£100+) if you don't have access to 12v from the genny. Mine cost ~£400 but has several features to help me not cook the batteries and I do rely on it for lighting and fridge + water.
That inverter still might not have enough juice to run the fridge/freezer. Check the continuous power rating as thats what really matters. My alledged 800 watt one gave up the ghost trying to run the freezer, as did my genny (not dead...just couldnt cope...but it is small).
Often the way you do it on a narrow boat is to have the alternator charging the batteries then convert that to ac with an inverter.
The other way is to have a 240v alternator but they aren't super and cost a lot.
Using the top system with propper thought and sufficiently expensive components() 12v lighting preheated water for the washing machine and other such optimisations you can get away with running the engine for a couple of a hours a day I'm told. Not done it myself though.
I would investigate how they do it on narrow boats as its very similar to what you are trying to do.
Bear in mind you need a good battery charger (£100+) if you don't have access to 12v from the genny. Mine cost ~£400 but has several features to help me not cook the batteries and I do rely on it for lighting and fridge + water.
That inverter still might not have enough juice to run the fridge/freezer. Check the continuous power rating as thats what really matters. My alledged 800 watt one gave up the ghost trying to run the freezer, as did my genny (not dead...just couldnt cope...but it is small).
Often the way you do it on a narrow boat is to have the alternator charging the batteries then convert that to ac with an inverter.
The other way is to have a 240v alternator but they aren't super and cost a lot.
Using the top system with propper thought and sufficiently expensive components
() 12v lighting preheated water for the washing machine and other such optimisations you can get away with running the engine for a couple of a hours a day I'm told. Not done it myself though.I would investigate how they do it on narrow boats as its very similar to what you are trying to do.
Yup, the altenator has a 240v output, looking at a sincro 6kva unit for just over £100 (then allow a bucket load for drivebelt fittings, etc)
Now where would be the fun in that? Besides I have this sitting down there at the moment:SB118 said:
Is that a dizzy i can see? spits on floor, throws salt over shoulder and kicks the cat
Bolt it to a frame, chuck some gogo juice in and you're laughing, it's not like you couldn't fit two or three 12v alternators into the space, one for the batteries, one to use and one for a charging circuit for anything you happen to be working on ... (i have come to love having a healthy 12v boost with the van in the manky weather!)
Bolt it to a frame, chuck some gogo juice in and you're laughing, it's not like you couldn't fit two or three 12v alternators into the space, one for the batteries, one to use and one for a charging circuit for anything you happen to be working on ... (i have come to love having a healthy 12v boost with the van in the manky weather!)
Exactly! An abandoned shopping trolley makes a perfect engine frame. Just need to raid the local exhaust place for a couple of silencers, don't want it disturbing my garage capers! Also need a bellhousing and a starter solenoid, got everything else down there already.
Although i admire the project from an engineering point of view, i have to wonder how much do you realistically expect to save from this - or is this not the point of it?
I only ask as my experience of utility bills is that they are not really very large, i run a 2 bedroom detached cottage in the middle of nowhere, the boiler runs on oil, and everything else is electric (cooker etc), so i'd imagine my house has to be less economical than a flat in a town? I just cant see that your costs are going to be re-couped, plus you have the added hassle of having to think about what load you are putting on your invertors all the time.
I only ask as my experience of utility bills is that they are not really very large, i run a 2 bedroom detached cottage in the middle of nowhere, the boiler runs on oil, and everything else is electric (cooker etc), so i'd imagine my house has to be less economical than a flat in a town? I just cant see that your costs are going to be re-couped, plus you have the added hassle of having to think about what load you are putting on your invertors all the time.
Jez said:
Once i've got the heat exchange side of things sorted, it's an immediate saving of £15/week as we won't need to run our calor gas fire. Not running this fire will also solve a LOT of the damp problems we have here (not nice to wake up and find water running down the windows of both bedrooms) Allow another £10-£15/week for electricity, maybe more when it's piddling down with rain all week and we use the tumble drier more.
Minimum saving of £25/week, the engine will be paid for in under a month, 5 weeks to cover the alternator (just grabbed an 8kva unit), allow another 5-6 weeks to pay off the inverter, then i'm hopefully putting money in the bank (or at least not taking so much out) Should all be done in under 4 months.
Most painful part is looking at the price difference between true sinewave and "modified" sinewave inverters
(prolly cheaper to get a couple of bigass UPS units and daisychain a load of deep soak batteries to them, only things that will need higher end power of an evening will be the telly and the fridge, hopefully the lights will be happy with cheapo inverter electric. It's a steep learning curve, i've already ordered the flowers for when she gets hacked off with the noise, not done any soundproofing yet!)
Soldato
Standard incandescant lights (the ones with a glowing filament in them) aren't fussed about sinewave or not. They can run off DC if you like. But you'll notice a lot less electricity useage with compact flourescents. I have them in all but three places in my house - the oven light, my wife's three stage bedlamp (dim-med-bright touch lamp), and one in the garage (CFL's don't do well below freezing, take forever to light).
One of the biggest full-time electrical users in your house will be the hot water heater. You can run a heat-exchanger from the engine coolant circuit. That solves that problem. Next will be heating. Run a couple radiators inside from the cooling circuit.
Next problem will be any heat-generating apliances - range, clothes dryer. An electric range with 4 elements on and the oven on bake will ba taking in excess of 30 amps at 220V. That's 6600 watts. Coming from your 12V battery bank, that's 550 amps. Not quite as bad is the clothes dryer, but it gets there.
Something you might want to look at is the possibility of dual power. Hook up a dedicated 7,500W 220V AC generator to the crank on the engine specifically to power the dryer and range. Then have everything else run through the inverter (or UPS - good idea there) which shouldn't add up to more than a couple thousand watts. I mean, the biggest users after the appliances will be the TV and the CPU (ok, the home entertainment if you've got enough wattage to shatter windows).
The trick is to limit all of your standby power you can. Those little walwart thingies (cell phone charger?) draw power. Unplug them or put them on a switched power line for when you're not actually using them. The TV on standby uses power (receiver for the remote signal). Same with the stereo, VCR, DVD player, etc. Anything with a remote. Have them all on a power bar so you can shut them completely down when not in use. Turn in your cordless phone for a standard wall plugged one. If you haven't already, exchange your standard CRT monitor for an LCD one.
I think you're getting the hint I'm trying to form here - conservation is a LOT CHEAPER than creating more power to cover these energy hogs I mentioned above.
I could go on and on about this for hours (I've been doing a lot of research for quite a few years), so I'll ask if you have any kind of instant messenger {I have the three main ones : ICQ - 5305805 , YIM - ov4rclok3r , MSN - sylvester_mack(at)hotmail(dot)com } if you want to add me and I can point you to several forums/websites that deal with this exact kind of thing.
One of the biggest full-time electrical users in your house will be the hot water heater. You can run a heat-exchanger from the engine coolant circuit. That solves that problem. Next will be heating. Run a couple radiators inside from the cooling circuit.
Next problem will be any heat-generating apliances - range, clothes dryer. An electric range with 4 elements on and the oven on bake will ba taking in excess of 30 amps at 220V. That's 6600 watts. Coming from your 12V battery bank, that's 550 amps. Not quite as bad is the clothes dryer, but it gets there.
Something you might want to look at is the possibility of dual power. Hook up a dedicated 7,500W 220V AC generator to the crank on the engine specifically to power the dryer and range. Then have everything else run through the inverter (or UPS - good idea there) which shouldn't add up to more than a couple thousand watts. I mean, the biggest users after the appliances will be the TV and the CPU (ok, the home entertainment if you've got enough wattage to shatter windows).
The trick is to limit all of your standby power you can. Those little walwart thingies (cell phone charger?) draw power. Unplug them or put them on a switched power line for when you're not actually using them. The TV on standby uses power (receiver for the remote signal). Same with the stereo, VCR, DVD player, etc. Anything with a remote. Have them all on a power bar so you can shut them completely down when not in use. Turn in your cordless phone for a standard wall plugged one. If you haven't already, exchange your standard CRT monitor for an LCD one.
I think you're getting the hint I'm trying to form here - conservation is a LOT CHEAPER than creating more power to cover these energy hogs I mentioned above.
I could go on and on about this for hours (I've been doing a lot of research for quite a few years), so I'll ask if you have any kind of instant messenger {I have the three main ones : ICQ - 5305805 , YIM - ov4rclok3r , MSN - sylvester_mack(at)hotmail(dot)com } if you want to add me and I can point you to several forums/websites that deal with this exact kind of thing.
Soldato
SB118 said:
This is the easy part. Go get two silencers from HGV's and bury them in sand with only the output showing above ground, then use an outdoor wood furnace chimney to route the gasses above roofline. Sorted. The noise coming from the actual generator will then be louder than the exhaust.......
One advantage to this is moles in your garden will no longer be a problem. The noise from the silencers transmitted to the ground will drive them bonkers and they'l go elsewhere!!!
Thanks for the tips, collant system heating will be when i get the next engine (she'll give in to shut me up in the end 
), this one is aircooled, so i need to either knock up and exhaust heatexchanger or just dip a big chunk of exhaust into a big tank of water and pump that through some radiators in the flat.
It's going into a concrete shed, but i'm going to pad out the interior to pacify the locals (it's great telling 'em to bogoff until they show up with the local council and a noise meter )
I'm still planning on running the genny during the day for all the household stuff, and then falling back on the inverter based kit for the evenings (fridge, telly, router and lappy chargers, looking to minimise all the current use), if we do all the domestic stuff during the day, we have to spend more quality time together in the evenings
), this one is aircooled, so i need to either knock up and exhaust heatexchanger or just dip a big chunk of exhaust into a big tank of water and pump that through some radiators in the flat.It's going into a concrete shed, but i'm going to pad out the interior to pacify the locals (it's great telling 'em to bogoff until they show up with the local council and a noise meter
)I'm still planning on running the genny during the day for all the household stuff, and then falling back on the inverter based kit for the evenings (fridge, telly, router and lappy chargers, looking to minimise all the current use), if we do all the domestic stuff during the day, we have to spend more quality time together in the evenings
Holy hell i wish i lived nearer to the guy selling me the alternator, going to be £33.50 + vat to get it delvered, damn thing is 45 kilos
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Look into narrow boat calorifiers. These are specificaly designed to transmit engine heat into a water tank. As to how much they cost I have no idea!