Should I get a reverse cycle air conditioner or a ducted gas heater for my new home?
Rowwwwy
| Posted in Energy Efficiency and Durability on
Hi,
I live in Perth Australia and I am building a SIPS Home, so it will be well insulated. I am concerned about heating the bottom story. I will install PV”s to offset some of my electricity costs. I hate being cold in the winter, but money is a big issue, so want to get the most heat for my money.
Ta,
Rowwwwy.
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Do you have natural gas piped to the property already, or were you talking about having a propane tank?
The lifecycle cost of PV power is cheap and getting cheaper, but in some areas natural gas is still price-competitive with PV + heat pump for space heating. Your actual heating loads and the price of gas/electricity need to be considered, but long term PV electricity will eventually become the cheapest energy of any type on a lifecycle output basis. If you have enough roof or garden area to put in enough PV to become net-energy-zero, it could be a very good thing. The installed price of grid-tied PV is likely to be about $1/watt in most of the developed world before the year 2020. (It's about twice that cost right now in Germany, 3-4x that much in the US- but I have no idea what it costs in Perth.)
I understand PV is very popular in western Australia- to the point that net-metered it's beginning to put serious financial stress on the western Australia grid operators (a good and bad thing), but that should hopefully get ironed out soon. (See: http://reneweconomy.com.au/2014/wa-grid-may-become-first-big-victim-of-death-spiral-41428 )
The highest efficiency heat pumps are the ductless "mini-split" type, which are cheap & rugged (if you buy a name brand like Daikin, Fujitsu, or Mitsubishi), but having local distributor & installer support for them would be a critical factor in decision making.
Having a room-by-room heating & cooling load calculation is critical for getting the sizing right, which is important for both efficiency and comfort.
Thank you so much for your answer. I will have plumbed in gas for my cooking and the builder was asking me if I was going to have a flued or unflued heater. If I have an unflued heater then I need a vent in the wall which undoes all the effort of building a SIPS house (well sealed and insulated). The flued heaters are very expensive (about the same price as an air conditioner), so I need to choose the cheaper option between gas or electricity. The Air con option will give us cool air in the Summer too. (It gets up to 36 degrees fairly often in Summer). We are going to put in Air con upstairs and a solar powered fan in the roof to suck out the heat from the ceiling and 2nd storey.
36 C = 96.8 F, I melt above 86 F =30 C
Cooler right now I am assuming... 16 C and showers says the Google, News says lightning strikes high winds most rain in years causing havoc... Western Power not enjoying it all.
Build that home well....
What is your retail energy pricing for both gas and electricity at this site?
Hi,
My electricity is 23.55 cents per unit (I use about 6 units per day and 7 in Summer) there is also a $25 supply charge, due quarterly.
My gas is more complex! This is what their website says-
Price Component Prices from
1 July 2013
(incl GST)
Residential Customers:
Supply charge 19.73 cents per day
Usage charge – for the first 12 units used on average per day 13.61 cents per unit
Usage charge – for each additional unit used on average per day 12.28 cents per unit
I hope that is of some help.
Rowena.
Rowena,
You have not defined what you mean by "unit." I assume that the unit for the sale of electricity in Australia is the kWh -- but you didn't tell us that. (If you are paying $0.24 Australian per kWh, that's equal to 22¢ in U.S. currency. In other words, that's fairly expensive electricity.)
We also need to know what you mean by a "unit" of natural gas.