Browse Forums Heating, Cooling & Insulation 1 Sep 10, 2008 12:02 pm Hi All,
I'm currently having the debate with my partner as to what type of air con to get. i want evap (i.e. cheaper to run! ) and he wants the brivis ice refrigerated cooling! I have been doing alot of researching and there is alot of info at how cheap it costs to run evap, but there isnt alot of info at how much it costs to run refrigerated cooling. the system we are looking at getting is the brivis ice 17.6 kw to 12 duct points! I'm just wanting an indication as to how much it would costs per hour/day to run! Cheers, Sam Re: Cost of running refrigerated air con! 2Nov 04, 2008 9:15 pm SammyJ Hi All, I'm currently having the debate with my partner as to what type of air con to get. i want evap (i.e. cheaper to run! ) and he wants the brivis ice refrigerated cooling! I have been doing alot of researching and there is alot of info at how cheap it costs to run evap, but there isnt alot of info at how much it costs to run refrigerated cooling. the system we are looking at getting is the brivis ice 17.6 kw to 12 duct points! I'm just wanting an indication as to how much it would costs per hour/day to run! Cheers, Sam Read this: http://www.sustainability.vic.gov.au/re ... system.pdf http://www.sustainability.vic.gov.au/re ... system.pdf Obviously it partly relates to you climate - predominantly heating or cooling. In most temperate climates heating is more than 3/4 of HVAC requirements. Re: Cost of running refrigerated air con! 3Nov 14, 2008 9:16 pm From my experience:
Evaporative - 5 to 10c per hour Refrigerated A/C - $1.00 to $1.20 per hour Huge difference! However on a humid day you will be cursing the evaporative cooler. In Melbourne you don't get too many though - so most people just 'deal with it' on those odd days and enjoy the cheaper running costs. Dynamic Heating & Cooling - http://www.DIYheating.com.au DIY Ducted Heating & Cooling Systems DIRECT to the public Re: Cost of running refrigerated air con! 4Nov 14, 2008 10:03 pm markDHC From my experience: Evaporative - 5 to 10c per hour Refrigerated A/C - $1.00 to $1.20 per hour Huge difference! However on a humid day you will be cursing the evaporative cooler. In Melbourne you don't get too many though - so most people just 'deal with it' on those odd days and enjoy the cheaper running costs. We have evap but switching to RCAC for our new house. RCAC gives you heating as well. Evap is cheap to run - it is basically a fan that pulls air through moistened straw. It's nice because you always drawing in fresh air and it is not so drying like RCAC (good for people with sensitive skin). It doesn't work in humid weather when the wet bulb temp isn't much difference from the dry bulb temp. The thing you need to watch out for is water consumption (which is also a big deal in our dry continent). Older units can go thru up to 600L in a day which is what a family of four could go through. The newer ones are more thrifty with water management system but you may need to do a bit of research. Re: Cost of running refrigerated air con! 5Nov 16, 2008 7:32 am SammyJ Hi All, I'm currently having the debate with my partner as to what type of air con to get. i want evap (i.e. cheaper to run! ) and he wants the brivis ice refrigerated cooling! I have been doing alot of researching and there is alot of info at how cheap it costs to run evap, but there isnt alot of info at how much it costs to run refrigerated cooling. the system we are looking at getting is the brivis ice 17.6 kw to 12 duct points! I'm just wanting an indication as to how much it would costs per hour/day to run! Cheers, Sam Have a look at this calculator... http://www.energyrating.gov.au/appsearch/air_srch.asp Re: Cost of running refrigerated air con! 6Nov 16, 2008 9:08 am Brand BRIVIS
Model IDU18A+CDU18A-9 Installation Type Single Split System, Ducted Phase Three Available AUS & NZ 10 Yr Energy Cost $1812 Output (kW) 17.13 Energy Input (kW 5.33 So if I read this right I am spending $180 dollars a year (on average) to keep cool..... I like it! Re: Cost of running refrigerated air con! 7Nov 16, 2008 12:04 pm mattwalker So if I read this right I am spending $180 dollars a year (on average) to keep cool..... You may wish to consider techniques of passively cooling your house and minimise the use of mechanical systems. http://www.yourhome.gov.au/technical/fs46.html Some tips are: - Foil under the roof - Foil in the walls (especially west facing) - Shading / Awnings over the windows - Vegetation in front of the walls - Painting the roof white or with heat reflective paint - Ceiling fans Our eco home has most of these things and comfortable even on a mid 30 degree day. The AC is only for backup Re: Cost of running refrigerated air con! 8Nov 16, 2008 12:21 pm dymonite69 The thing you need to watch out for is water consumption (which is also a big deal in our dry continent). Older units can go thru up to 600L in a day which is what a family of four could go through. The newer ones are more thrifty with water management system but you may need to do a bit of research. I think this is slightly misrepresentative...it'd have to be pretty old for that sort of consumption...newer ones would be less than 200 litres per day...and that's only days it's being used... mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Re: Cost of running refrigerated air con! 9Nov 16, 2008 2:06 pm to_do_list dymonite69 I think this is slightly misrepresentative...it'd have to be pretty old for that sort of consumption...newer ones would be less than 200 litres per day...and that's only days it's being used... Depends on what you read. That's why I said do your research. http://www.lmw.vic.gov.au/html/document ... 11007a.pdf http://www.yvw.com.au/NR/rdonlyres/823F ... Report.pdf Re: Cost of running refrigerated air con! 10Nov 16, 2008 3:24 pm Yes...I read the Yarra Valley report and that's why I'd say your misrepresenting the facts...
Quoting the report.... Because of the small sample size together with the large variation in usage (daily usage ranged from 81 to 304 litres per day), it is not possible to conclude which type of unit delivers greater efficiency overall. The extent of the variation however suggests there is scope for the development of minimum efficiency standards for this appliance. Furthermore the unit that delivered usage of 600 litres per day was distorted by one unit which ran continuosly, independent of temperature. I would contend that any new unit would be on the lower end of the usage range and don't have the high dump and bleed off rates of newer units. As an Environmental Lobiest (I presume you mean Lobbyist) on http://forums.envirotalk.com.au/Turns-P ... t7724.html wouldn't you argue that if you are going to adopt air conditioning as an active method of cooling then evaporative should be considered well ahead of refrigerated due to the electricity consumption and therefore emissions. Perhaps you don't mean to but you are using statistics selectively..... you argue evaporative is high water usage...without also stating that whilst refrigerated uses no water it is high in electricity consumption and therefore messes with the environment in another way. mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Re: Cost of running refrigerated air con! 11Nov 16, 2008 6:04 pm dymonite69 You may wish to consider techniques of passively cooling your house and minimise the use of mechanical systems. Yep! I considered it ... and I really really like my ducted A/C. I could not care if it cost $500 a year as long as I, and my family, are comfortable! Passive is definately not for me Re: Cost of running refrigerated air con! 12Nov 16, 2008 6:07 pm to_do_list Furthermore the unit that delivered usage of 600 litres per day was distorted by one unit which ran continuosly, independent of temperature. I would contend that any new unit would be on the lower end of the usage range and don't have the high dump and bleed off rates of newer units. As an Environmental Lobiest (I presume you mean Lobbyist) on http://forums.envirotalk.com.au/Turns-P ... t7724.html wouldn't you argue that if you are going to adopt air conditioning as an active method of cooling then evaporative should be considered well ahead of refrigerated due to the electricity consumption and therefore emissions. Perhaps you don't mean to but you are using statistics selectively..... you argue evaporative is high water usage...without also stating that whilst refrigerated uses no water it is high in electricity consumption and therefore messes with the environment in another way. Hi To do list, Those appellations next to my name are added by the forum. I don't particularly lobby anyone! The figure I quoted was used in hyperbole to highlight issues that may not be considered. You may be quite correct in mentioning that new units are very conservative with water. However, it is also possible that there are old units in operation out there where the valves haven't been checked for ages and are indeed wasting water. I have already given balance to the argument by mentioning that evaporative cooling doesn't need much energy to run. My point is that when discussing the environmental impact of various things we need to consider a whole raft of issues and not just focus on one thing e.g. embodied energy, life cycle, recyclability, pollution, running costs etc etc. Rather than arguing one point I just present what are the facts currently at hand and let people make up their own mind. Balancing water use and energy use may in some situations not be a simple answer. Re: Cost of running refrigerated air con! 13Nov 16, 2008 7:33 pm dymonite69 Hi To do list, Those appellations next to my name are added by the forum. I don't particularly lobby anyone! Gotcha...like our gold member...junior member...bronze member....apologies I misunderstood where you are coming from. dymonite69 The figure I quoted was used in hyperbole to highlight issues that may not be considered. I get concerned when numbers like that is put out without the qualification...someone may be tossing up evaporative airconditioning on the basis of energy consumption and may dismiss it on the basis of water use...when they see a number like that taken from a small sample. The Lower Murray Water example is also a completely different environment...sustained heat over long months combined with a perilous water situation in the Murray-Darling system...but imagine if they all went refridgerated... the balance between people's comfort and environmental outcomes is difficult. dymonite69 You may be quite correct in mentioning that new units are very conservative with water. However, it is also possible that there are old units in operation out there where the valves haven't been checked for ages and are indeed wasting water. I have already given balance to the argument by mentioning that evaporative cooling doesn't need much energy to run. You've now qualified the high usage rates which was my intent. dymonite69 My point is that when discussing the environmental impact of various things we need to consider a whole raft of issues and not just focus on one thing e.g. embodied energy, life cycle, recyclability, pollution, running costs etc etc. Rather than arguing one point I just present what are the facts currently at hand and let people make up their own mind. Balancing water use and energy use may in some situations not be a simple answer. Providing the balance to the argument (and qualifying where possible) is what fora are all about...and I think we've successfully done that...I've enjoyed the discussion... mmm....donuts Homer Simpson 1956- Links: Site Costs Ready Reckoner | H1 Addiction Medical Advice | Château TDL: The Backyard Re: Cost of running refrigerated air con! 15Mar 03, 2009 7:57 pm TheBoatMan Look for Power Imput (Rated) Obviously this varies depending on 1) cost of power and 2) how often the compressor cycles off. To put these figures into perspective. A 4.8kW A/C probably could condition about 50m2. If running at 60% then it will consume 0.6 x 4.8 = 2.9kwh per hour. Running for 12 hrs a day then it will be 35 kWh This equals the TOTAL energy consumption of an average household in Australia. This off course assumes that the compressor is cycling on for 60% of the time. Treat your house like a fridge because that's exactly how the Refrigerative AC works. Things that will increase the workload of the compressor: a) Excessive heat entering the house in the first place - inadequate shading and awnings, no reflective foil in the ceiling and walls, large areas of paving and concrete around the house radiating heat inwards b) Airleaks out of the house (same effect as leaving the fridge door open) c) Very hot weather (more difficulty to push the heat back out again) d) Compressor located in a hot or sunny location (e.g. roof space, non-shady side of the house) e) Thermostat set too low (more heat needs to be removed to get to the set-point) Therefore your compressor needs to work harder to keep the heat out, it won't last as long, energy consumption can increase > 50% and your bills will be higher. Simple solutions are: 1) Weatherseal your house for air leaks. Close windows and doors when AC is on 2) Plant more trees/shrubs near the house. Remove heat islands 3) Shading the windows and walls from direct sunlight 4) Put reflective foil under the roof (may save up to 20% in energy costs) 5) Set your thermostat 1 or 2 degrees higher (running a ceiling fan will allow you to get the same cooling effect for a higher thermostat setting) Once you have removed the initial excess heat from the house and taken several measure to prevent further heat re-entering then your aircon may not need to run much of the time to maintain comfortable temperatures. Re: Cost of running refrigerated air con! 16Mar 03, 2009 9:11 pm Im with Matt, cost is no object when it comes to staying comfortable, especially when you have young children, you spend so much on a place, you may as well always be comfy Blog - http://snakedr.blogspot.com/ Build Thread - viewtopic.php?f=31&t=12084&p=307406#p307406 Status - PCI 15/10. Things nearly done. Re: Cost of running refrigerated air con! 17Mar 03, 2009 9:29 pm billdsl Im with Matt, cost is no object when it comes to staying comfortable, especially when you have young children, you spend so much on a place, you may as well always be comfy Yet it is a pity that people won't place a small investment in addtional passive design features in the house to extend the life of their air-conditioner and get many useful years from it. An energy efficient house can consume at least a third in energy costs yet maintain the same comfort conditions from the same heating/cooling system. The only difference is the thought and care that goes into the design and construction. Given enough energy one can make even a cardboard box habitable in the most extreme environment. Look at what the Saudis can achieve in the middle of the desert! However, one day they will run out of the black stuff and who knows what will happen then? Re: Cost of running refrigerated air con! 18Mar 03, 2009 10:44 pm i don't understand how passive cooling is going to do sfa to combat off the tree humidity though, eaves, allowing for wind flow, house position, none of this is going to do a thing when there's no breeze and humidity is in the 80's
i think desert dwellers just love having sweaty underwear... or is that why they wear what they do, no underwear? Blog - http://snakedr.blogspot.com/ Build Thread - viewtopic.php?f=31&t=12084&p=307406#p307406 Status - PCI 15/10. Things nearly done. Re: Cost of running refrigerated air con! 19Mar 03, 2009 11:22 pm billdsl i don't understand how passive cooling is going to do sfa to combat off the tree humidity though Humid environments are always a challenge! There is now research where the two mechanisms of excess heat is addressed separately i.e sensible heat (high air temperatures) and latent head (humidity). Most standard air conditioner achieve both but you can't control how much of each you control. By balancing these independently you can achieve comfort levels whilst expending less energy. In some systems a dedicated dehumidifier brings comfort levels to tolerable levels so that things like cheap-running fans can actually work. These systems have shown to maintain comfort using less energy than what a standard air conditioner can achieve. Some of the better air-cons can achieve a similar effect using the 'dry mode'. You can prioritise humidity reduction over air cooling. These were intially marketed toward humid places such as Thailand Nevertheless a reasonably air tight house can maintain the air temperature and humidity that the air con has already established. If there are large air leaks, the air con constantly has to work to remove the incoming hot, moist air. Re: Cost of running refrigerated air con! 20Mar 04, 2009 11:30 pm Ipswich humid ??? Not often IMO.
Lack of rain is the main issue there. Hot dry summers and cold in winter IMO. Yes I've been there many times. Try planting lots of trees around the house, encourage shade and airflow, and insulate the house to stop heat gain - and lock it up for winter and alos on hot summer days to keep the heat out. How do you remove one of these ceiling air con vents? And is it possible to disconnect the duct joined to the vent from inside the house, without going into the roof cavity? 0 5900 Hi all, sorting out the ducted air con for a 350sqm double story house. Does this placement sound reasonable to you? Also, I plan to have 6 zones I think. Living room… 0 0 Hi all, sorting out the ducted air con for a 350sqm double story house. I think i plan to have 6 zones I think. Living room (mainly for entertainment so not used often),… 0 0 |