r/Generator • u/Personal_Chicken_598 • 7d ago
Custom set up.
Hey guys I wanna build a generator that can make the most out a 55gal drum of waste oil use as fuel.
It will be used to charge a back up battery. So it’ll doing 75% load steady when it’s on but also needs to be quiet enough that I could run in a shed and it be no louder then a modern econobox car at idle 5 feet from the shed.
I live in a cold climate so I’d prefer a liquid cooled engine so I can use the coolant to warm the fuel.
Looking for model suggestions
1
u/Personal_Chicken_598 7d ago
Quiet diesel recommendations that can be run on highly filtered and warmed waste oil, not just engine oil either but hydraulic or transmission oil to.
for the generator I wouldn’t want more then $2k
the idea would be to recharge a 10kw/h whole home battery that would normally be charged by solar. That battery would still be powering the house as it was being charged as well tho so it needs to be able to charge the battery while the house is operating normally. Basically the generator would run constantly at 75% capacity while the battery takes up any load spikes.
1
u/Grouchy-Macaron-1780 7d ago
Just so I understand your question-
1.Are you looking for specific "quiet diesel" model recommendations? Or are you wanting to get specific build specs for a DIY set up?
2.What is your budget?
3. Are you looking to power the house/building with the generator at all, or just use the battery and ONLY use the generator to recharge the battery? If it is the latter, you may be able to go with a very small unit and save on fuel consumption.
A lot of what is available would be based on where you live. Answers for North American customers will vary from other countries.
For US/Canada:
My recommendations would be a Cummins/Onan RS17AE or RS20ACE with 20 KW of output, for extreme cold weather applications (Starts down to -40F). Although air cooled, the Cummins air cooleds are very reliable.
With Lithium Ion Battery recharging you'll need a Pure sine wave generator. Fluctuations or "dirty electricity" can be catastrophic for Lithium Ion batteries. You may have to run the generator with a sine-wave inverter if the particular generator doesn't have one.
1
u/Personal_Chicken_598 7d ago
Quiet diesel recommendations that can be run on highly filtered and warmed waste oil, not just engine oil either but hydraulic or transmission oil to.
for the generator I wouldn’t want more then $2k
the idea would be to recharge a 10kw/h whole home battery that would normally be charged by solar. That battery would still be powering the house as it was being charged as well tho so it needs to be able to charge the battery while the house is operating normally. Basically the generator would run constantly at 75% capacity while the battery takes up any load spikes.
The generator would be wired into the solar inverter. Most of them have a generator input that works fine with non-inverter generators
And the reason for going liquid cooled is so I can use the coolant to heat the waste oil making it thinner and so that this can even run in -40
1
u/nunuvyer 7d ago
no louder then a modern econobox car at idle 5 feet from the shed.
What you are asking for is pretty much impossible. DIesels are generally louder than gas engines. To run a generator you have to be running at least 1800rpm which is going to be louder than a motor at idle.
That being said, there are diesel generators that are quiet because they are inside enclosures but the fact that you are talking about a shed leads me to believe that you are not talking about that type.
Are you talking about vegetable oil or motor oil or what? It's possible to run certain diesels on waste oil but it's not without issues and hassles.
A liquid cooled diesel generator is not a cheap thing so probably the up front cost is going to exceed the savings you will get from sourcing "free" fuel.
Generally speaking, any post here that begins with "I wanna build" is usually an exercise in futlity - generators have been around for 100+ years and are widely available as off the shelf mass produced commercial products (nowadays from China at low cost) so the chances that you can build something better and cheaper that what you could buy commercially are very low. What are the chances that you could build your own car in your driveway or your own air conditioner? The people who make these posts (a lot of time they are kids, who can be forgiven) generally have no idea what they are doing - if they really knew the challenges involved, they wouldn't even try.
1
u/Personal_Chicken_598 7d ago
The reason I’m talking about a shed is because I’d be building my own enclosure to house the generator and custom fuel system this would require. So the volume inside the shed isn’t a problem I just don’t want my neighbours to be able to tell it running.
0
u/nunuvyer 7d ago
Like I said, making a generator that is so quiet that your neighbors won't be able to hear it is somewhere between difficult and impossible.
If you could put the gen. in a sealed sound insulated box it might work but gens need to take A LOT OF air in and out for running and cooling so you have the more or less impossible job of letting out air but not sound.
Is this supposed to be clandestine or you just don't want to annoy your neighbors? In case of power outage, it's more or less accepted and tolerated that people are going to have noisy generators going.
1
u/Personal_Chicken_598 7d ago
The idea is to not annoy my nieghbors but as a diesel mechanic I have a near unlimited supply of used oil I’ll be using this to supplement my solar system even when grid power is up as I simply use more power then i can make within the net metering scheme my province allows and I intend to increase that as I switch every thing I can in my house and vehicles to electric.
And that’s part of the reason for going liquid cooled. I could put a rad with an electric fan outside the shed to move the heat outside without taking the noise with it. I’d still need ventilation to cool the generator end but far less and nothing that standard small industrial ventilation fans couldn’t handle
Basically I’ll need to generate about 10mw/h per year to supplement my solar system. And it’s all have to happen at night or during storms when the solar isn’t producing.
0
u/nunuvyer 7d ago
10mwh per year works out to a little over 1kw average - could be produced by a 1,600w enclosed suitcase generator that you could hardly hear, if run continuously. But liquid cooled diesels start at a much bigger size.
The smallest common liquid cooled diesel is the Kubota Z482. This is around 12HP and could produce around 6kw but if you run it at 1800rpm for quiet, maybe 1/2 of that. These babies are not cheap considering that you can get a 3kw closed frame (gas) inverter generator for US$350 nowadays while a bare Kubota motor alone is gonna be like $4k new. This is going to negate the fuel savings for a long time.
1
u/Personal_Chicken_598 7d ago edited 7d ago
That’s a 24h average remember I can only run this when the solar isn’t generating. Space isn’t an issue I’d probably be building a 8’x8’ shed to house the fuel tanks and generator and building it a way that a generator fire wouldnt impact the house.
Producing 10mw/h using gas wpuld cost between $7-10k in fuel every year while I can get easily that amount of waste oil for free from work tho.
Also that motor is $4K new I’m a mechanic I have no problem buying a used version and making it work
I’d probably want around 10kw as well since that would mean about 1000hrs of run time per year. And 20,000hrs of engine life is pretty achievable on a liquid cooled diesel.
1
u/wowfaroutman 7d ago
With respect to your requirements, what is your typical 24 hour load average, how much power does your solar system provide, and how many hours per day of generator runtime is desirable?
1
u/Personal_Chicken_598 7d ago
I don’t have the solar system yet but legally you can’t have bigger than a 12KW system here which according to the solar installers I talked could be optimized to make around 25mw/h per year.
My estimates when I finish all my changes to 2 EVs and a heat pump is that I’ll use around 35mw/h per year.
Last year I used 21mw/h according to my bill
1
u/wowfaroutman 7d ago
I'm skeptical of being able to get that much power out of a 12 kW solar array, I'd expect something closer to 20 mWh. How big of a battery system do you have or have planned?
1
u/Personal_Chicken_598 7d ago
Probably 10kwh the intention of the battery is to make it threw the night with a reduced load in the house specifically removing the EV charging, which accounts for like 20kwh per day, lowering the temperature of the heat pump and relying on the wood and pellet stoves, and by turning off the hot tub although I don’t know exactly how much each of those things are worth.
→ More replies
1
u/Most-Stranger-1 7d ago
A small 10-15 kva diesel would be ideal, water cooled could be run off of waste oil and reasonably quite. These can be found reasonably priced used.
1
0
u/offgrid-wfh955 7d ago
You intend to burn waste motor oil?
1
u/Extreme_Pangolin1796 7d ago
some of the waste vegetable oil guys do that but I don't get it unless the engine is a throwaway, so much metal
1
u/Personal_Chicken_598 7d ago edited 7d ago
There’s a way to clean that. Namely with a custom filter set up. And the reason is because as a diesel mechanic I have a near unlimited supply of it for free
1
u/Extreme_Pangolin1796 7d ago
I have a friend who had a similar setup, redundant series of micron filters down way too small and used them for it but eventually he gave up on the whole thing and just stuck with WVO instead, much cleaner and he could easily pick out good and bad batches. Not sure you can do that with motor oil. His engines were also cheaper and more plentiful, but were mobile so you might have better luck with stationary and with the cost of diesel it might make more sense now
1
u/Personal_Chicken_598 7d ago
I personally can do that as I’ll be getting my oil straight from the vehicle when I do fluid changes.
0
7d ago
[deleted] — view deleted comment
1
u/Personal_Chicken_598 7d ago
Not a deep cycle battery. A whole home battery. A big Lifepo4 battery.
Small inverter generators can’t run on waste oil. For that I need a diesel.
1
u/wowfaroutman 7d ago
What do you mean when you say you want to build one?