Did an audit on a house the other day using 50kWh/day pretty much all year round. Fancy renovations but no attention to efficiency via insulation etc - huge glass windows with no coverings and they wonder why its cold.
They have a "small" pool with heat pump, about 2x5m x 1.5mdeep (?) Hard to read the label on the heat pump but I think it said output 10kW and COP 5, so about 2kW input. She will only swim in the pool when its heated - to about 29C - so its a big spa rather than small pool! They admit it sometimes takes a couple of days to heat up ! So that could be 48kWh/day. I'm going to put a logger on their meter for a week to get more info' but I was wondering about doing the energy requirements calculations form another angle.
I know 1kWh will heat 20litres from 20C to 60C - so as an equivalent to thermal heat coeff type calculations, we could say 1kWh will give 20x40 = 800LdegC of heating or 0.8kLdegC. So if the pool is 15kL, to heat it 1degC would need 15/0.8 = 18.75kWh. Heating by say 8C would need 150kWh. But with COP 5 the actual consumption would be 30kWh which sounds about right when you allow for heat losses while heating - the heat pump is about 20m away from the pool with plain poly pipe so they're probably heating all the concrete in between too!
Anyone had any experience with similar situations ?
Pool heating
(5 posts) (4 voices)-
Benny
MemberPosted Tuesday 26 May 2015 @ 12:35:16 am from IP # -
Morbo
Memberyou not just heating the water, but also the soil around the pond and the air on top. At 50kWh a day maybe a trigeneration plant is not a bad idea. 50kWh a day, I love it, when people got more money than brains. Their energy bill would be big enough for a small campfire.
Posted Saturday 14 Nov 2015 @ 9:08:02 pm from IP # -
axess
MemberHi Benny,
I had a client once who was using 52kWh/day. His aircon turned out to be the major culprit but at least these clients are seeking help which is great.
Could you also put a logger on the pool heater power source? They don't have a sauna as well do they, with an electric heater?
It will be interesting to follow this story.
Posted Sunday 15 Nov 2015 @ 3:55:24 am from IP # -
Morbo
Member2kW aircon running all day, 48kWh there. Aircon doing nothing all day, 1kWh stanby load, I realised that, when I swiched its circuit breaker off. Another 1kWh stanby load. 2kWh doing roast. Gas cooking or electrical? Fancy fridge, 2kWh a day easily. And so on. Colleague complained about $750 a quarter, thats my annual power bill....
Posted Sunday 15 Nov 2015 @ 4:52:45 am from IP # -
Oilburner
MemberPretty amazing consumption figures.
I'm sure these people are the 20% of domestic customers that make up 80% of the power companies profits.My wife and i went and looked at a house we were seriously interested in 2 weeks ago. Awsome place, a real lifestyles of the rich and famous job. I counted 8 split aircons in the place. Down one side of the house there are 4 outdoor units lined up in a row and another 2 at the front and another 2 on the other side. They didn have a heat pump for the hot water for the laundry and 2 ensuits but for the upper level they had a normal hot water service for the bathroom and main bedroom ensuite.
The pool and the sunken spa were both heated with a massive heat pump arrangement which was 3 phase and the kitchen and bathroom in the Cabana had another 125L hot water heater.
The place was a real summer house with mi9les of glass and concertina windows but as I said to my wife, would be a damn expensive place to run. There were no solar panels of any type probably due to the amount of trees around the place. Along with the land size, the power needs of the place would make it perfect for my DIY proclivities. I would need a lot of oil to power that joint though none the less.I wonder if many people can actually visualize power? For me it's easy. I play with and build my own generators. I have a Lister Engine that will do up to 3 Kw but is happier and obviously more under stressed doing 2.
50 Kwh day is running that thing non stop at 2/3 output all day and night.That is a lot of running and power. Even if people are not influenced by the cost of this level of consumption, I bet they would be if they had to tend a generator and fuel and maintain it and got a tangible feedback on the sort of KW they are using.
OTOH, the Lister would put out a good 2 Kw of heat as well so they could put a HE on that and heat the pool and save doubly there.
I use a lot of power at home too. We have a drier, 2 Split air-cons, Large pool and a bunch of always running electrical appliances. I run the lister a few hours a day, a few days a week during the week and maybe the better part of a day when when I'm around weekends and our power bill works out at 4 Kwh/day. According to what is on the power bill, an average 4 person home is 19 Kw from memory.I was thinking about setting up a co-gen system a while back with a 5 Cylinder Diesel engine driving a genny and heating the pool. The problem would be I'd have to put in a heavy duty circuit to be able to generate enough power to put a decent load on the engine to get some worthwhile heat out of it. I have a couple of 2 Kw and a 5 Kw solar inverters I can feed the power though but no 5K + circuits to run it back though. Also, if I over shoot the amount of power we use, the electric company will probably get sus and come and give me a hard time.
All good and well to save power and be green and all that BS as long as it makes them money. Can't have too many people being too self sufficient and independent, no profit in that!
Posted Tuesday 17 Nov 2015 @ 11:08:17 am from IP #