Shore power KW usage

[a64pilot]

Originally Posted by TCM1968

Your calculations are based of the 1 ton a/c running at the lowest temp setting and at full load 24 hrs/day. From about 6pm to 10am which is 16 hours of the 24 it keeps up normally and cycles on and off. It’s only during the hottest hours of the day the it rarely cycles the compressor off. And like I said my 2500 sq/ft poorly insulated house with a 5 ton a/c running in the same climate and a 5hp swimming pool pump running 14 hours a day, electric water heater on always, my electric kw usage was the same this month as the boat. Last month my boat electric bill was only 70.00 . Something is fishy. I am going to install a kw meter on the boat and start comparing to the marina numbers.

Yes, remember that one ton is only 12,000 BTU, his boat has five AC’s maybe 5 16,000 BTU ones? I would have though fewer but larger, but don’t know his boat.
Anyway when he leaves he leaves three running.
I think he isn’t doing bad actually.

[TCM1968]

Originally Posted by a64pilot

Yes, remember that one ton is only 12,000 BTU, his boat has five AC’s maybe 5 16,000 BTU ones? I would have though fewer but larger, but don’t know his boat.
Anyway when he leaves he leaves three running.
I think he isn’t doing bad actually.

When I leave only one is left running. Three when we are on the boat. The one a/c left on is a 16000 btu unit and I am an electrician so I do understand the BTU to kw conversion and that conversion is based on maximum thermal conversion by the unit which is not doing the majority of the time running. Otherwise the 5ton unit in my home that runs constantly during the summer except for night time loads would run my home electric usage to triple that of the boat and that would be if only the a/c were running.

[sailorboy1]

If I ran my 16k air conditioner continuous all month it would use 1,166 KWh

So throw in refrigeration and running a couple more air conditioners I can see getting to 1,700 kWh

[Seymore]

Read your meter yourself every month, to check on the staff readings.

I'm in a marina where they charged a power boat owner (about) $163 for electricity for a month one summer. The owner had nothing running. It turned out the staff member had no idea how to read an electric meter.

My electric bill had been fluctuating all over the place. I then read my meter myself and submitted the month's electric consumption with my slip rent check. The electric consumption straightened right out and the management couldn't argue with that.

.

[kas_1611]

Holy AC Batman!!

I have a 5 bedroom house in NW Scotland that uses 2530 kwhr per YEAR. That covers 2 induction hobs, including a 7.5kw one, 2 electric ovens and all the usual electrical and electronic gizmos and gadgets you find in a home.

1700 a month just for an AC unit? Just goes to prove just how much energy is wasted by Air Conditioning.

I pay a total of £380 a year for my electricity from renewable sources if it is of interest.

Perhaps there in lies a solution to your energy problem. Put some big solar panels and maybe a wind generator on your boat to power your AC rather than use the mains. Or switch off all the ACs when you aren't onboard.

[Pete7]

Surely this is case for some white sun shades for the time you are not on board or not moving. Be interesting to see what the difference is, but keeping the sun off the deck would be high on my list.

Normally we run the diesel heating when away our summer holidays each August, but we do have a white tarp for the boom ready to go to keep the sun off just in case.

As it happens summer in the UK this year is this Saturday we will need the sun shade as it's going to reach 31c that's nearly 88f

Pete

[ebs001]

Originally Posted by TCM1968

Your calculations are based of the 1 ton a/c running at the lowest temp setting and at full load 24 hrs/day. From about 6pm to 10am which is 16 hours of the 24 it keeps up normally and cycles on and off. It’s only during the hottest hours of the day the it rarely cycles the compressor off. And like I said my 2500 sq/ft poorly insulated house with a 5 ton a/c running in the same climate and a 5hp swimming pool pump running 14 hours a day, electric water heater on always, my electric kw usage was the same this month as the boat. Last month my boat electric bill was only 70.00 . Something is fishy. I am going to install a kw meter on the boat and start comparing to the marina numbers.

Your 5 ton a/c uses 5.5KW. The 5HP motor consumes 4.66KW. Your pool heater about 3KW. You are consuming about 13KW per hour. 13 x 30 = 390 KWH @ $0.07/KWH = $27.3 for one hour's full operation per day. Something is fishy. Your pool pump alone should cost you $137.

[Dockhead]

As others have said -- sounds very cheap to me. $172 a month? $0.10 per kW/h is outstandingly cheap -- less than the average COST in the U.S. AFAIK. The kW/h consumption also sounds about right to me for, as others have said, a poorly insulated boat in a hot as hell place.



But there's a real simple answer -- just install an accumulating power meter and measure it yourself. You can buy a metered shore power cable, like this: https://www.force4.co.uk/32amp-15m-lead-master-m.html


Or install a power meter on your main electrical panel.

[TCM1968]

Originally Posted by Dockhead

As others have said -- sounds very cheap to me. $172 a month? $0.10 per kW/h is outstandingly cheap -- less than the average COST in the U.S. AFAIK. The kW/h consumption also sounds about right to me for, as others have said, a poorly insulated boat in a hot as hell place.



But there's a real simple answer -- just install an accumulating power meter and measure it yourself. You can buy a metered shore power cable, like this: https://www.force4.co.uk/32amp-15m-lead-master-m.html


Or install a power meter on your main electrical panel.

I will be installing a metering device soon. In the mean time I was hoping for some real life comparisons to others with a similar setup to mine. Not really interested in someone’s mathematical calculations based from generic equations from the internet or if someone thinks I should be happy because electricity is cheaper here than where they are. If my marina is not properly reading my usage then that’s a problem and I would like to address it. As I had mentioned earlier my bill from the previous month under the same usage conditions as this last month, and same weather conditions, was less then half of of this months bill. So either the marina messed up reading meters or I have developed an electrical issue on the boat consuming way more energy than normal, which is a possibility on a 23 year old boat.

So there may have been some misunderstanding in my OP as to what I was asking.

[sailorboy1]

Originally Posted by TCM1968

So there may have been some misunderstanding in my OP as to what I was asking.

OK

Near as I can answer is the only time I was at a marina for a full month billing period where electric was billed separate it cost me $167. Pretty much all of that was running a 16k btu air conditioner.

[TCM1968]

Dollars are irrelevant as electricity rates are different everywhere. Do you know the KW you used? And were you on the boat all month or just part of the time?

[sailorboy1]

was on the boat full time and I told all I have

I bet on a boat with 4 air conditioners that a 16k runs more often is the only on than on a boat with 2 units

I'm unsubscribing now as I don't have the answer you want

[Scubaseas]

Just got my bill from the marina. Thought you might like to know electric use was:


May was 127KW @ .069= $8.79
June was 247KW @ .069= 16.29


Note I was not on the boat during either months. A/C is set to 78*F, boat is 42' monohull in Seabrook Texas with a single 12000BTU airmarine unit. Fridge is also running full time. V berth and forward head doors are closed and all hatches outside have Sunbrella covers. Me thinks one or more of your units ain't right. Especially if you used $70 the month before. Or the meter ain't right.



Or maybe my meter ain't right




HTH

Al

[a64pilot]

Just for something to think about.
After lunch but before the hottest part of the day, I got my IR thermometer out, started walking around pointing it at the ceiling, mostly got mid 80’s temps but a few hot spots about 93.
Interior boat temp outside of the AC airflow was 78f.
Went outside, the surface temp on deck was 145f as was the temp of the concrete floating dock, I guess my deck is better insulated than I realized.
However the dark green Sunbrella cover I have on my hatch covers was 173F.
Water temp being real dark here is I think about 90f, so my hull having no insulation is 90f.
So I’m cooling a boat to mid 70’s while the entire shell is 90 or above.

[Scubaseas]

Originally Posted by a64pilot

Just for something to think about.
After lunch but before the hottest part of the day, I got my IR thermometer out, started walking around pointing it at the ceiling, mostly got mid 80’s temps but a few hot spots about 93.
Interior boat temp outside of the AC airflow was 78f.
Went outside, the surface temp on deck was 145f as was the temp of the concrete floating dock, I guess my deck is better insulated than I realized.
However the dark green Sunbrella cover I have on my hatch covers was 173F.
Water temp being real dark here is I think about 90f, so my hull having no insulation is 90f.
So I’m cooling a boat to mid 70’s while the entire shell is 90 or above.

Just for fun, how many KW/month are you using?