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Propane Generator Grid Tie

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Grid-tie when it's distributed is all over the map for the utility. If the utility has control, then genrally no problem. The "old school" way of syncing a generator was to put a light bulb between them, You engaged them when the bulb was out. Once it was synced, it would be OK.

The grid tie inverter AS to shut off when the line goes down and you can't try to supply the entire substation or kill a lineman working on the power lines.

Hence, grid tie with backup is a lot more expensive. DC is the intermediary. Batteries may come into play as well if you want bumpless transfers.

Some systems can mange multiple inputs such as wind, solar, batteries, local hydro and utility power.

From a utility perspective. nuclear and hydro provide the base power.
Wind, you have to take when you can get it.
Natural gas is throttle-able.
Coal is is bit slower to throttle.
Inverter technology, you can take it, leave it or store it.
 
What are you hoping to achieve?, I fail to see the point of generating expensive electricity and then selling it cheaply to the grid?.

Or are you claiming you can generate it cheaper than you get paid for it? - which I don't believe anyone has managed using internal combustion?.
 
What are you hoping to achieve?, I fail to see the point of generating expensive electricity and then selling it cheaply to the grid?.

Or are you claiming you can generate it cheaper than you get paid for it? - which I don't believe anyone has managed using internal combustion?.

That's the problem. I can't make my own as cheaply as I can buy it. :) That does not even begin to take into consideration mechanical maintenance as tcmtech mentions, just in fossil fuel along I lose.

Ron
 
yesyes i get what we are saying there, but we cannot define profit without expenses first, but there is product and it has purpose:
I found a data sheet for this one:
**broken link removed**

First would this work?
Is it quiet for urban life?
What is installation & certification costs(not by me!)?

lol, if i act now:
**broken link removed**

only 90 hrs!:
**broken link removed**
but no shipping to CA:( which i seem to run to problem alot lately

but again what do i need to get it to grid? Are these ones synchronous or do i need to get extra? lots of different routes , but which is all around cheapest?
 
**broken link removed**

480/277 3 phase?

CA puts you in an entirely different world, especially emissions. In CA, items may not even qualify as paper weight.
 
Around here a basic legal grid feedback metering systems would put at least $50 a month on to the basic connection price.

Logistically figure a gallon of propane will give you about 10 KWH's of electrical power to feed back providing you have a very efficient engine and system design.

Now factor in that very few utility companies are going to pay you more than their bulk rate for you power which to be honest might be between 2 and 8 cents a KWH.
Next figure what your propane is going to cost you. I just filled my bulk tank and got the summer low at 95 cents a gallon.

Last figure that with a small sized IC engine based systems your base operating cost not including purchase costs will run you 1 - 2 cents a KWH.

Right there you are looking at a operating cost of at least 10 - 13 cents a KWH to make 2 - 8 cents worth of electricity to feed back.

Add in that realistically you could spend $3000 - $4000 minimum up front plus have a $60 - $100+ a month connection fee on top of that and if you are really lucky your system lasts for 20,000 running hours (about 2.25 years) you coul dhave a total start to finish 20,000 hour run time investment of around $5000 - $8000+ in machinery and fees plus fuel costs on top of all of that to make 2 - 8 cent a KWH electricity for 10 - 13 cents a KWH.

Realistically just assume that for every KWH you sell back you spend a dime more than what ever they pay you in return.

About the only time doing co gen becomes profitable is if you can sell back power at rates of 100+ KWH per hour and your primary fuel source is free and your system can run for 10 - 20+ years between major overhauls.
 
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Busted, you are rite, i found the biogas system, and contacted the pros they say the same , finally i am able to crunch that number for yall:

in Canada:
http://www.ontarioenergyboard.ca/OEB/Consumers/Natural+Gas/Natural+Gas+Rates
the cost of natural gas is 11 cents per m^3

I found a 85kwh gen for specs purpose:
**broken link removed**
this generator uses 11m^3 per hr, and at 11 cents, that works out to 1.21/hr to fuel

at that rate of consumption it puts out 85kwh.

Now check this out, i wonder if the payout is even better outside my country, the sales guy said generators are more popular in Europe countries:
**broken link removed**

going by that my 85kwh generator tied to grid as 20 cents per kw,
= 17 $/ hour
= 148000 per year

plus according to sales guy, initial investment is about 100,000$ to get started, so thats money back in 2/3 year plus profit for the next 10yrs

still a very profitable investment. I think I heard a research study on solar once, it was something like you buy a solar kit which lasts 24 yrs, in average sun it takes about 9 yrs for return on your investment, after that you only get another 16yrs which is about 1.5x original investment that comes back as profit, if these are the cases gas is the way to go.

still, usually price is linear with size, so i can take that 85kwh system and divide all by 10, so my revenue is still 14,000 $ /yr (although shorter lifespans on equipment), i ll try to crunch this later to see the differences.

PLus , I initially thought buying gas from gas co and selling to hydro would be on the illegal side, but its actually essential for the system (due to the lower methane ratio in bio fuel).
 
here is math i do on low end engine:
http://www.centralmainediesel.com/order/Honda-10kw-Propane-Generator.asp?page=H04590

1.2 gallon/hr = 0.0054553 m^3/hr = nil
10kw
2 year warrenty :)!!
2200 $ cost
plus 2200$ for grid inverter (average)
easy installation
grid tie 1000$ one time payment

still about 6000$ /2yrs that i need to invest
= 2$/hr
= 17,000$ per year profit

only problem here is that these generators are at 75 db, which is prolly too loud for my home use.

no?
 
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only problem here is that these generators are at 75 db, which is prolly too loud for my home use.

no?

No. As I recall those Honda engines are maybe good for 3000 - 4000 running hours under ideal maintenance and work load conditions when running on propane.

Air cooled and high RPM does not equal long engine life. Big heavy slow and liquid cooled does.

If you want durability find a old oil field heavy flywheel engine like an Atlas, Fairbanks Morse or other huge slow running single cylinder natural gas hit and miss style engine.


It will drive your neighbors nuts but the thing will probably run nonstop for 10 - 15 years between rebuilds.
 
So how does someone get into this 20 cent a KWH buyback program in Canada?

I'm curious being for me Canada is only an hour or so away from me and I have loads of equipment at hand and with easy access to more that for me would be no major financial outlay or investment to move to some small Canadian town just across the border that has a Natural Gas system and set up a hundred plus KWH co gen system for easy money as long as the buy back program is in effect.
 
I doubt anyone will give you the subsidized 20 cents/kW if you are making the power by burning propane. These programs are usually for renewable sources only, try finding some numbers for generation witout subsidy. How much do you pay for electricity at home?
 
That's my thoughts on this as well otherwise every person who has a large NG fueled genset for backup power would be getting setup for grid feedback and be raking in a pile of money through this program.
 
Ok so i just said propane as a throw, since most if not all propane engines work with NG, look at the link from the hydro company, it is BIOFUEL that pays out soo much:
my target for this thread was just to to get a working system and needed help to cut out as many components as I could for cost purposes.

The rates posted were for Ontario specifically, but the sales guy was from Alberta, idk what they do out there, but in ON you need to apply to 2 ppl, hydro, and microfet, plus then you need the safety inspections , (that was for solar) also i will double check, for now im going off memory for all this. Also i think the first 2 applications are to ensure you are in the right area to tie in with proper systems, and that solar cells are not reflecting in to buildings and such.

Also again, I initially thought that buying from gas co, burning and reselling would be illegal due to some emission standard, but it turns out you NEED to do it, so really you only need 1 chicken or even dog(!) to claim it as biofuel.

Also there is 1 other catch i forgot to mention, return rate = amount generated - amount consumed, ie they take the amount generated and minus what you consumed before paying, so my figure is only accurate if the property has no electrical consumption, cos when i buy my own energy to use for my self , i am paying that high rate. which means i will need separate address' for consumption and generation.

Also it would not surprise me if these rates are for promotional purposes as well and will drop when it becomes more popular, I didn't look to see if they were fixed yet.

My cost here for hydro is 8c/kwh and 12c during business hours
Natrual gas through the pipe is 11c/m^3, at union gas
 
Also it would not surprise me if these rates are for promotional purposes as well and will drop when it becomes more popular, I didn't look to see if they were fixed yet.
UK feed-in tariffs are on a sliding scale, reducing over 20 years. Domestic tariffs also depend on the (officially checked) energy efficiency of the dwelling, being lower for dwellings with poorer efficiency.
 
Also again, I initially thought that buying from gas co, burning and reselling would be illegal due to some emission standard, but it turns out you NEED to do it, so really you only need 1 chicken or even dog(!) to claim it as biofuel.

Do you have any documentation or reference links that elaborate on that aspect far more clearly as in the ratio of true bio produced fuel gas to utility supplied NG or other purchased fuel?
 
no, but he mentioned that since there is excess c02 in the bio that it needs to be enriched with the pipe fuel, to avoid backfire, they will not calculate beyond that, but my figures reflect a system not using bio gas at all, or would if i hadnt forgotten to subtract the 1.2$ from 17$ before multiplying my hours,

in any rate the problem in bio fuel is that its too difficult to accurately calculate the ratio of ch4 to co2. and any dung added in will just factor in some extra free kw's,
If your asking from a legal standpoint then im not sure , but I would guess to compare it to the fire law here, ie, in city you can only have an outdoor fire if its contained and for cooking purposes, ie you need to leave a grill and some buns laying around in the yard.
just guess thou.

if you are talking cost wise, then you will still get the total energy out if you burned the pipe gas separately then burned "co2-free purified biogas" and added together.

The reason bio cant be calculated properly is due to different things being in digester and health of digester itself, however if you are a true farmer with more than 1 cow i have done a production estimate based on rough numbers, very rough, again though bio energy is just additional icing for the true NG system.

Infact I recently wondered how much cow farts depleted the ozone layer, although i wasnt able to get the volume of farts produced per day, but i was able to get some dung calculations

Scan22.jpg Scan.jpg


pretty much , a full sized cow is about 2400 lbs, and poops 240 lbs per day
cow dung holds about 200L of BIOGAS per 2.2lbs or 100L/lbs
so we have about 24,000 L of bio gas for 1 cow per day

for cow biogas 68% of that is methane, so we get 68L/lbs of cows waste
which works out to 16,000L of pure methane per cow per day
OR 7L of pure methane per pound of cow you own.
OR 0.007 m^3 per pound of cow per day

so to generate 100kw each hour per day we would need 37000 lbs worth of cow, or 15 cows.

again if you look at the figures, the biogas isnt the part of the equation that makes this valuable. As the machine only needs 11m^3/hr of gas or 1.21$/hr of gas. to generate that 17$/hr revenue (15.8$ running off the pipe)

Also it was interesting to look at the charts of all the things that do produce biogas, and which ones had better co2 ratios
 
so we have about 24,000 L of bio gas for 1 cow per day

I think the gas numbers are off by a factor of 100 or more and the poop numbers by a factor of 10 at least.

At 24,000 liters a day that would mean one cow has to pass something like ~16.6 liters of gas a minute.

As someone who has been around cattle I can assure you they dont even breath 16.6 liters of air a minute let alone fart that much and for an animal that eats at most 30 - 50 pounds of grass a day I am doubtful on can make 240 pounds of poop from that and 5 - 10 gallons of water.
 
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