diy solar

diy solar

Solar and batteries or generator when grid goes down?

My Generator is in my shop exhaust to the outside 100 foot away!
I don’t have that luxury. My lot is a zero-setback on the sides, so technically the generator is not on my property. It's easier to ask for forgiveness than for permission ?. I'll screw a couple of training wheels to the side and claim its a portable.
 
Always Let it rest!
I agree to let it rest while I change the oil and filter every 4 to 10 days.

Generator only works while you have fuel. Could get a smaller battery system to immediately provide power while the generator gets up to speed or needs service. I like multiple systems when preparing for an emergency. Great to hear the generator was a success.
 
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Generators are a very cost effective solution for backup power, and many off-grid homes will have one as they supply their own grid and that sometimes needs supplemental energy support.

But generators are not always a suitable solution, for instance in urban areas where noise pollution is an issue. And some people are less comfortable using a generator (refuelling, basic maintenance, even starting it if not automated).

I set up a generator backup system which worked great but my wife was not at all comfortable using it. If I was not at home when the grid went down, she would not use it. This became more pointed when we built a home for my elderly mother on our land and I did not want her to be without power just because I wasn't there.

So I wanted a backup system my wife was good with and could easily operate if I was not here. The off-grid solar PV & battery system means she only needs to flip one switch and that's it. No need to pull a generator out, start it, or refuel it. It operates silently and doesn't require refuelling. The system can also be put into Utility pass through mode to automate the cut over to backup if we feel that is desirable at times (I normally don't use that mode as it limits the power we can draw).

Of course if an outage is very long and the weather poor for solar PV production to keep the batteries sufficiently charged, then I still have the option of providing supplemental energy to the system with my generator.

This is actually a really efficient use of the generator as two hours of generator operation will supply about eight hours of backup energy into the battery. Else if we were using a generator alone it would need to be running for those eight hours.
 
Lots of companies make no hassle standby generators. They auto start when the power goes out, and stop when it's back on. Provide it a source of natural gas or propane and no worry about fuel going bad.
 
Will I disagree. I let my car, motorcycle, tractor etc. rest. It has to cool down to check or change the oil. More wear I would say No. That makes no sense to me at all! Not changing the oil at 100 hours would cause wear. Not letting it REST!
Stopping. Cooling down. Restarting.

This will cause the most amount of wear any engine will see and each event is the equivalent of dozens of hours of run time.

An engine experiences the most wear prior to coming up to operating temp. After it's up to temperature it's operating under the design conditions and all clearances and fluid viscosity will be as intended for the longest life.

It might not make sense to you but that's only due to lack of knowledge. Metals expand and contract under temperature changes and the clearances are designed to be loose when cool and the engine has drained its oil into its sump, which means every start is momentarily starved for oil.

Do not do this.

Source: mechanical engineering school and a decade of experience running equipment 24/7.

I do several times as much maintenance on the machines that are shutdown frequently than the ones that just stay running forever.
 
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Lots of companies make no hassle standby generators. They auto start when the power goes out, and stop when it's back on. Provide it a source of natural gas or propane and no worry about fuel going bad.
Yes they do (e.g. Generac) and they are seemingly fairly common in the US but here in Australia they are more expensive to install than a grid tied battery system which is why at household level they are pretty rare here.

Here the generators used for home backup tend to not be these "no hassle" type systems, rather they are more your standard type of portable generator running on petrol or diesel.

Also generators which run on methane or propane are also not common and usually require an imported after market conversion kit. I looked into it as the thought of running off a standard propane gas tank had its appeal but the cost of importing a kit from US was ridiculous, let alone the risk of me screwing up my perfectly functioning generator. It was just cheaper to build an off-grid solar PV and battery system.
 
Also generators which run on methane or propane are also not common and usually require an imported after market conversion kit. I looked into it as the thought of running off a standard propane gas tank had its appeal but the cost of importing a kit from US was ridiculous, let alone the risk of me screwing up my perfectly functioning generator.

You can often DIY your own conversion. It can be as simple as an on-demand propane regulator and sticking a tube into the carb intake. I have two small inverter generators I do this with. Since there is no modification to anything, it won't hurt the generator.
 
You can often DIY your own conversion. It can be as simple as an on-demand propane regulator and sticking a tube into the carb intake. I have two small inverter generators I do this with. Since there is no modification to anything, it won't hurt the generator.
I looked into it. Such kits for my generator are available in the US for about US$160. Cheap as chips.

To get one here costs nearly A$600.

$600 got me a 4kW off-grid inverter plus enough change for the DC cabling. Rest of my stuff was pre-loved kit and cheap.

In any case I cycle though my petrol fairly regularly (my yard is a 3.5 to 4 hour mow job) so stale fuel isn't an issue.
 
Stopping. Cooling down. Restarting.

This will cause the most amount of wear any engine will see and each event is the equivalent of dozens of hours of run time.

An engine experiences the most wear prior to coming up to operating temp. After it's up to temperature it's operating under the design conditions and all clearances and fluid viscosity will be as intended for the longest life.

It might not make sense to you but that's only due to lack of knowledge. Metals expand and contract under temperature changes and the clearances are designed to be loose when cool and the engine has drained its oil into its sump, which means every start is momentarily starved for oil.

Do not do this.

Source: mechanical engineering school and a decade of experience running equipment 24/7.

I do several times as much maintenance on the machines that are shutdown frequently than the ones that just stay running forever.
Home generators have an optional “cold weather kit" including a block heater. In theory the heater can be reconfigured to maintain the engine temperature closer to operating temperature.

For a generator that cycles on an hourly basis, the block heater should consume minimal power to maintain the temperature. At least here in the deep south the engine will lose minimal heat. Would not recommend for a diesel engine as they require combustion heat.
 

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Home generators have an optional “cold weather kit" including a block heater. In theory the heater can be reconfigured to maintain the engine temperature closer to operating temperature.

For a generator that cycles on an hourly basis, the block heater should consume minimal power to maintain the temperature. At least here in the deep south the engine will lose minimal heat.
Yep.

That's a good thing to have, sure. But while it reduces the effects of cycling the engine it doesn't eliminate them.

Some systems go as far as to pre-circulate the oil as well.
 
Yep.

That's a good thing to have, sure. But while it reduces the effects of cycling the engine it doesn't eliminate them.

Some systems go as far as to pre-circulate the oil as well.
The opposite problem of cycling is continuous operation under minimal load, especially with diesel engines. Reference article.

I purposefully undersized my 14kw Generac to start a 3-ton AC where the charts recommend a 18kw. It grunts a bit but has no problem starting the compressor.
 
Let me add this, a gasoline generator half the size of mine will not run an electric dryer or a central air conditioner and will cost you over twice as much. A 20k Generac will also cost twice as much but you can run anything. I have two 2 ton A/Cs one upstairs and one downstairs. So I can easily run either but not both. National gas is the way to go for me. I live out in the country and have my Generator in a Shed 100 foot away. The 14k handled everything and we were comfortable. No gas to buy and have to pour into a hot Generator at 2AM.
 
Let me add this, a gasoline generator half the size of mine will not run an electric dryer or a central air conditioner and will cost you over twice as much. A 20k Generac will also cost twice as much but you can run anything. I have two 2 ton A/Cs one upstairs and one downstairs. So I can easily run either but not both. National gas is the way to go for me. I live out in the country and have my Generator in a Shed 100 foot away. The 14k handled everything and we were comfortable. No gas to buy and have to pour into a hot Generator at 2AM.
I'm absolutely a big fan of natural gas gens for home use.

I have yet to hear of natural gas going down in a crisis. Not to say it can't happen of course.
 
Generators are a very cost effective solution for backup power, and many off-grid homes will have one as they supply their own grid and that sometimes needs supplemental energy support.

But generators are not always a suitable solution, for instance in urban areas where noise pollution is an issue. And some people are less comfortable using a generator (refuelling, basic maintenance, even starting it if not automated).

I set up a generator backup system which worked great but my wife was not at all comfortable using it. If I was not at home when the grid went down, she would not use it. This became more pointed when we built a home for my elderly mother on our land and I did not want her to be without power just because I wasn't there.

So I wanted a backup system my wife was good with and could easily operate if I was not here. The off-grid solar PV & battery system means she only needs to flip one switch and that's it. No need to pull a generator out, start it, or refuel it. It operates silently and doesn't require refuelling. The system can also be put into Utility pass through mode to automate the cut over to backup if we feel that is desirable at times (I normally don't use that mode as it limits the power we can draw).

Of course if an outage is very long and the weather poor for solar PV production to keep the batteries sufficiently charged, then I still have the option of providing supplemental energy to the system with my generator.

This is actually a really efficient use of the generator as two hours of generator operation will supply about eight hours of backup energy into the battery. Else if we were using a generator alone it would need to be running for those eight hours.
Sounds good, can you run an electric dryer or central A/C or just lights, TV and refrigerator? You could always start the Generator for bigger stuff if batteries can't handle everything!
 
Here is a screenshot from my FB page of just a few of the people here, I have over 100 comments and all are similar.
 

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I think the biggest advantage of battery backup is convenience. When the power goes down or glitches, the loads on my subpanel never see it. The computers, video recorder, televisions, and some lights don't go down while the generator spins up. It is in effect a mostly whole-house UPS.
 
I'm not worried about the cost so much as availability.
It's the lack of availability which is driving the cost. Classic supply/demand curve. Basically China is hoovering up the world supply of available natural gas while that nice Mr. Putin is stepping on the pipelines to throttle what's coming out of the East...

Winter is going to be "interesting" :unsure:
 
It's the lack of availability which is driving the cost. Classic supply/demand curve. Basically China is hoovering up the world supply of available natural gas while that nice Mr. Putin is stepping on the pipelines to throttle what's coming out of the East...

Winter is going to be "interesting" :unsure:
I'll clarify further.

When the gas stops coming out of the pipes and going into my generator that's when I'll worry about it.

Raising prices because it's a bit more scarce does not a shutoff make.
 
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