Cost to run my generator.

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jann

Senior Member
Joined
Apr 23, 2012
Messages
111
Location
usa
Gentlemen

For information only

I have a Mainship 34t with a Kohler 8KW.

I wanted to know how much it cost to run the generator, so I made a test.

I have a level gauge on my fuel tank which I calibrated to give me fuel usage.

I ran the test during a cruise for 12 hrs with Refrigerator and both AC's on ( ie. full load.)

My results was .4 gal of Diesel fuel per hour. at ~ $4.00 per gal. comes to ~ $1.60 per hour...not bad.
 
Those figures you have quoted are about what we get using our Onan 7KVA at half load.

On full load we use about 2.7 litres (US .65 gallons) per hour.

You either have a very efficient generator, or your gen is not running under full load for the entire test period.
 
We also have an 8kW Kohler. Our nominal fuel burn under load is .7 US gallons/hour. The total cost of running the generator of course includes the additional cost of oil and filter changes, as well as repair and replacement costs. In the US, at current average diesel prices of about $4.30/gallon, and an estimated lifetime of 10,000 hours, with a replacement cost of about $11,000, your actual operating cost will be roughly 50% greater than your fuel cost alone. We mitigate this cost by running a little Honda 2000i gasoline generator as our backup unit when our power needs are small (to charge batteries, make coffee, watch tv, make popcorn, etc.). This saves enormously on fuel and operating expenses as the Honda will run all night long under moderate load burning 1 Imperial gallon, or 1.1 US gallons, with a unit replacement cost of roughly $900. The little guy makes plenty of power whether the sun is shining or not, and whether the wind is blowing or not. Yet it costs less than a moderate size wind generator, or solar panel array. You may want to investigate getting one as a backup. We've found it has paid for itself many times over. Good luck!
 
I run a 30 yr old Westerbeke which runs .5 gallons an hour. I love it. Diesel is the key.
 
In a different way of looking at generator usage cost, we figure each night at anchor in these days of $4 diesel costs us $25. When you take the fuel cost of running the generator for the 2-4 hours we typically need along with the other costs like Captain K described, that's what comes out for us.

So having that number is very useful when evaluating marina costs. There are many marinas where a week and certainly a month stay will cost less than $25 per day. That makes it less expensive for us to stay at the marina than to anchor out. Or even evaluating anchoring versus staying as a one-night transient. It's not the cost of the slip. It's the cost minus $25 that we're really paying to stay at the marina (if we need to run the generator).
 
In a different way of looking at generator usage cost, we figure each night at anchor in these days of $4 diesel costs us $25. When you take the fuel cost of running the generator for the 2-4 hours we typically need along with the other costs like Captain K described, that's what comes out for us.

So having that number is very useful when evaluating marina costs. There are many marinas where a week and certainly a month stay will cost less than $25 per day. That makes it less expensive for us to stay at the marina than to anchor out. Or even evaluating anchoring versus staying as a one-night transient. It's not the cost of the slip. It's the cost minus $25 that we're really paying to stay at the marina (if we need to run the generator).

ActiveCaptain, as much as you're my hero... And all that. Anchoring is fun. Marinas are what they are. The dudes at Barefoot were like Frick and Frack. Newbies, and I shoulda insisted on going inside. Must be early in the season.

Keep up the good work.
 
Anchoring is fun. Marinas are what they are. The dudes at Barefoot were like Frick and Frack. Newbies, and I shoulda insisted on going inside.
Heck, few trawler owners like anchoring more than me - we just anchored last night - here's the time lapse from the Butler Island anchorage to Osprey Marina this morning:
Butler Island - Osprey Marina - YouTube

But there are times when you really need the facilities of a marina. Or when the weather really demands it. Or your wife demands it.

Truth be told, we spend too much time in marinas these days - mostly because we're visiting the ones we work with to learn what's happening and understand their business.

I'm not sure what happened at Barefoot. We'll be there tomorrow. Bill, the manager, goes over every review they get to understand issues and fix them. If something went wrong, make sure they know - they'd honestly want to fix it.
 
Heck, few trawler owners like anchoring more than me - we just anchored last night - here's the time lapse from the Butler Island anchorage to Osprey Marina this morning:
Butler Island - Osprey Marina - YouTube

But there are times when you really need the facilities of a marina. Or when the weather really demands it. Or your wife demands it.

Truth be told, we spend too much time in marinas these days - mostly because we're visiting the ones we work with to learn what's happening and understand their business.

I'm not sure what happened at Barefoot. We'll be there tomorrow. Bill, the manager, goes over every review they get to understand issues and fix them. If something went wrong, make sure they know - they'd honestly want to fix it.

Bill is an awesome guy.. He always takes care of us. For years he has done so.
yesterday our experience was as if they had never heard of a transient.

The two guys who met us had never tied up a boat. Starboard tie and where? We ended up on the face dock.

Woody
 
Captain K

Love my Honda 2000 Honda generator, but I won't have it aboard.

Two reasons.....have to store gasoline ( dangerous ) but most importantly...carbon monoxide

When I had my 30 mainship without a genset...I used to use it.

I remember one night both CO monitor went off together.

Be careful with this little guy.
 
Excellent point jann. You are justified in being cautious of both gasoline and CO. Our strategy is to treat both with utmost respect. In consequence, we have enjoyed many years of safe boating with our little Honda. We keep all gasoline (including outboard fuel) stored outside, NEVER below decks. And we only run our Honda outside on the boat deck aft where its exhaust is carried clear of the vessel. At anchor, where we most often lie head to wind, the Honda's exhaust carries off to lee naturally and dissipates. But we make sure our CO detectors have fresh batteries and are in proper working order. Caveat Emptor!
 
Just a few generator numbers:

Kohler 9kw Full load 1.05 gph, half load 0.53
Kohler 20 kw Full 1.49, half 0.83
Northern Lights 20kw Full 1.7 half 1.0
Northern Lights 30kw Full 2.8 half 1.5
Northern Lights 99kw Full 7.9 half 4.1

Just examples and most generator manufacturers have fuel usage on spec sheets on their sites.
 
Excellent point jann. You are justified in being cautious of both gasoline and CO. Our strategy is to treat both with utmost respect. In consequence, we have enjoyed many years of safe boating with our little Honda. We keep all gasoline (including outboard fuel) stored outside, NEVER below decks. And we only run our Honda outside on the boat deck aft where its exhaust is carried clear of the vessel. At anchor, where we most often lie head to wind, the Honda's exhaust carries off to lee naturally and dissipates. But we make sure our CO detectors have fresh batteries and are in proper working order. Caveat Emptor!

My Honda eu2000i is my only generator. I use it primarily to power the microwave, Keurig coffee maker and charge batteries. It sits high on the a FB bench, secured to the side rail with the exhaust aft about 8-9 ft above the deck. We only run it during waking hours and find that the exhaust dissipates very well from that position. Since we already have gas safely stored on board for our dinghy motor, it wasn't an issue for us. Ditto on the CO detectors, but they're powered by the house bank which is charging with the generator.

All generators require common sense and safety practices to mitigate risks.
 
I have a Mainship 34t with a Kohler 8KW.

I ran the test during a cruise for 12 hrs with Refrigerator and both AC's on ( ie. full load.)

My results was .4 gal of Diesel fuel per hour. at ~ $4.00 per gal. comes to ~ $1.60 per hour...not bad.


Interesting.

We can run two ACs, two fridges, hot water heater, stovetop, microwave/convection oven, toaster, the battery charger, and various lights/TVs/etc. all at once with out 8 kW Kohler. Although I'm sure many time the various compressors and heating elements and so forth aren't all really on at the same time...

-Chris
 
Please excuse my knuckle dragging ignorance, but doesn't the Honda 2000 put out 8 amps in 12 volt DC, or 13.3 amps in 120 AC (through a shorepower cord adapter to an inverter/charger)...so, if you had to put 100 amp hours back into your 12 volt battery bank, wouldn't it take 12.5 hours at 8 amps, or 7.5 hours at 13.3 amps?

Or...would you just chuck in enough to keep the batteries "pretty much" topped up, and charge them fully when next underway with the main engine?
 
As to the Kohler 8 kw getting .4 gph at "Full Load". Be careful defining full load. Yes, you had everything on, but that doesn't mean it was requiring 8 kw at all times. Per Kohler's own numbers you were probably averaging around half a load, using about 4 kw. But that is typical. Seldom will we require everything a generator has. That doesn't just require everything on, but probably us using everything or really starting things up at the same time. I would imagine you probably had a peak usage during that time of 6 kw and a low of 3 kw and it averaged around 4.
 
Murray- If you run the boat charger off the Honda 120v output, it's charge rate can be way higher than 8A. The 8A is just if you hook up to the 12v output directly.
 
Please excuse my knuckle dragging ignorance, but doesn't the Honda 2000 put out 8 amps in 12 volt DC, or 13.3 amps in 120 AC (through a shorepower cord adapter to an inverter/charger)...so, if you had to put 100 amp hours back into your 12 volt battery bank, wouldn't it take 12.5 hours at 8 amps, or 7.5 hours at 13.3 amps?

Or...would you just chuck in enough to keep the batteries "pretty much" topped up, and charge them fully when next underway with the main engine?

Ski's right.

I don't know anyone on a boat using the 12V circuitry to charge at 8 amps. I have the Honda cord with battery clamps, but have never used it. It might come in handy for charging a car battery in the boonies, though.

I use the 120V power which is limited to 13.3A/1600W continuous output. That 1600W would translate into about 130A at 12V with no losses, but figure 115-120A @ 12V for purposes of discussion. Lots of guys have 12V 100A chargers, but I don't know any running them on a Honda. It would cause the unit to run at or near high RPM which can be a bit noisy and annoying. I came close to buying one, but had a change of heart after analyzing the loads.

I run a 55A charger with it and it hardly revs up on eco throttle to provide that power. I need about 150A per day, so if I'm not running the engines, I'll need about 3-4 hrs of gen time to replace it. Just about the right amount of time for making meals and heating water, too. (Although I can heat water a lot faster with an main engine run than by using electrics alone.)
 
Ski's right.

I don't know anyone on a boat using the 12V circuitry to charge at 8 amps. I have the Honda cord with battery clamps, but have never used it. It might come in handy for charging a car battery in the boonies, though.

I use the 120V power which is limited to 13.3A/1600W continuous output. That 1600W would translate into about 130A at 12V with no losses, but figure 115-120A @ 12V for purposes of discussion. Lots of guys have 12V 100A chargers, but I don't know any running them on a Honda. It would cause the unit to run at or near high RPM which can be a bit noisy and annoying. I came close to buying one, but had a change of heart after analyzing the loads.

I run a 55A charger with it and it hardly revs up on eco throttle to provide that power. I need about 150A per day, so if I'm not running the engines, I'll need about 3-4 hrs of gen time to replace it. Just about the right amount of time for making meals and heating water, too. (Although I can heat water a lot faster with an main engine run than by using electrics alone.)

They work great for charging batteries. Ours will push the 50 amp Heart Freedom 10 charger/inverter and our Pro Mariner 40 amp charger both at the same time. We've used our Honda to charge our batteries many times with no issues. It burns way less fuel than our main 8kw Onan Genset and is 100% reliable. Great little unit to have along as a backup.
 
I think there's a confusion between amps at 12v and amps at 120v. Watts is a better measure than amps because of this.

The Honda 2000 series is called the 2000 series because it puts out 2000 watts. 2000 / 12 = 167 amps at 12v. Of course there will be some loss but it'll surely put out 100 amps at 12v which is a good amount to charge battery banks on many types of trawlers.
 
I think there's a confusion between amps at 12v and amps at 120v. Watts is a better measure than amps because of this.

The Honda 2000 series is called the 2000 series because it puts out 2000 watts. 2000 / 12 = 167 amps at 12v. Of course there will be some loss but it'll surely put out 100 amps at 12v which is a good amount to charge battery banks on many types of trawlers.

No doubt the marketing folks had a hand in naming these and similar units.

It puts out 2000W peak, but only 1600W continuous. The 12V output is just 8A/96W...not enough to do much with. It's really a gas-powered inverter putting out its best power at 120V which is limited to 13.3A/1600W continuous.

Still enough to power a 100A charger, though.
 
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I think there's a confusion between amps at 12v and amps at 120v. Watts is a better measure than amps because of this.

The Honda 2000 series is called the 2000 series because it puts out 2000 watts. 2000 / 12 = 167 amps at 12v. Of course there will be some loss but it'll surely put out 100 amps at 12v which is a good amount to charge battery banks on many types of trawlers.

The Honda 2000 puts out 1600-2000 watts at 120v not 12v.
 
Quick question from newbie. I get a puff of blue smoke whenever I start my honda eu2000 ever since new. Does everyone else , or does it have an issue? Otherwise runs fine.
 
When my choke is on, it sputters and smokes just for a moment, then with the choke off, no smoke at all.
 
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I’m a sailboat cruiser about to go to the dark side. Having a hard time wrapping my head around relying on a generator where I am accustomed to spending 90% of my still time at anchor using solar and wind power. First question: has anyone converted their electric stove to propane?
 
... First question: has anyone converted their electric stove to propane?

We did and it was pretty easy. There are guidelines you need to follow for a safe, compliant installation but all the parts are easily sourced. Storing the propane and routing the hose from the tank to the stove was hardest part.
 
I’m a sailboat cruiser about to go to the dark side. Having a hard time wrapping my head around relying on a generator where I am accustomed to spending 90% of my still time at anchor using solar and wind power. First question: has anyone converted their electric stove to propane?

There is no reason you can't install solar and wind generation. Many, many trawlers have solar panels.

Honestly, I think that generators were more slowly adopted on sailboats for a few reasons. Traditionally they didn't have them. sailboats have a tougher time placing them due to space than trawlers do. Sailboats have traditionally small fuel tankage, introducing the need for more space.

Trawlers already had a big engine, fuel tankage, and space. Adding a generator became more logical.

PS- It's not 'The Dark Side' to us. We have lights....and cold drinks....and A/C.....and generators ;)
 
The other big difference is that sail boats already had a relatively small and efficient engine so just increasing alternator output and adding inverter capacity was a logical direction vs installing generators.
 
I’m a sailboat cruiser about to go to the dark side. Having a hard time wrapping my head around relying on a generator where I am accustomed to spending 90% of my still time at anchor using solar and wind power. First question: has anyone converted their electric stove to propane?


First of all, many trawlers with electric stoves also have gensets. Coming from a sailing background this may offend your sensibilities, but running a genset for cooking, water heating, microwave use and recharging batteries makes a lot of sense. When I had my 34' trawler that was all electric, I ran the genset about 45 minutes morning and night and that covered all of those needs.


But if the trawler you select has an electric stove but no genset then it is straightforward changing the stove to propane, but as noted above location of the propane locker and routing the propane line can be tough.


On many trawlers, putting a propane locker right behind the fly bridge seating is the best option. You can buy a locker made just for that purpose. Install it so the drain at the bottom goes overboard.


You then need a solenoid valve and a pressure gauge at the propane bottle. These are available as a package from Trident and others. You run the propane hose and the wiring for the solenoid to the galley and hook up the hose to your new propane stove. Then install a solenoid switch to control the gas from the galley. This is a safety feature that lets you keep your gas shut off when you are not using it.


Some users intall a propane leak detector in that circuit that shuts down the solenoid when it detects a leak, but I have found the detectors to be unreliable and I wouldn't have one. ABYC does not require one, just the solenoid valve controlled by a switch in the galley.


David.
 
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