Home Owner’s Guide to Free Gas Heating

TL; DR. No there’s no free natural gas but there’s free electricity, hope you don’t mind heating up your rooms with reverse cycle air conditioners instead

My old house had an equally old gas heater, and we had been using it for years. 4 years ago, the heater broke down, so I had it replaced with a newer model. The newer model is more efficient however as the natural gas price skyrocketed it actually costed me more money than the old one, about A$700 for last winter. The heater itself costed around A$2k so it felt like I will pay for a new heater every 3 years. How wonderful.

As a long time solar power user, I surely did my own research on electric heating:

  • the old school electric heaters with heating elements are the cheapest to buy but least efficient to run(coefficient of performance < 100%). Surprise?
  • the air conditioners with reverse cycle capability are expensive to buy but very efficient to run. The coefficient of performance usually exceeds 200% because it use energy to transfer heat, not generating heat.
  • the air conditioners with inverter design are even more efficient(> 300%), as it speeds up/down the compressor based on demand instead of turning it on/off.

On the other hand, something about duct gas heating:

  • it heats up the house faster than ACs generally
  • the vents on the floor are more effective than high hanging AC units as hot air goes up
  • it generates heat from burning natural gas, the exhaust is both hot and toxic, and the hotter the exhaust is the less efficient the heater is. Regardless, the coefficient of performance is highly likely lower than 100%
  • it also consumes power to push hot air through ducts, in my case, up to 1kw
  • the ducts need to be well insulated otherwise some heat is lost before reaching vents, so more maintenance is needed in the long run

So I got 3 ACs installed. they are capable to heat up rooms almost as fast as my old gas heater did. The power consumption peaks at around 3.3kw and later will sustain at around 1.5kw. Just remember this, the gas heater used 1kw just for the powerful fan to deliver heat through ducts. Bye bye natural gas.

But where’s the free electricity coming from? There’s Globird’s Free Lunch electricity plan! In a nutshell using electricity between 12PM to 2PM is free of charge. Usually a single phase residential circuit can allow up to 63A of current which translates to about 15kw of power, so in 2 hours one can have up to 30kwh of free power. You can over heat/cool your house during this period and then only use minimal power to top up afterwards. And obviously you can time power-hungry appliances such as dish-washer, oven, etc. to run in these 2 hours too. If this sounds interesting, you can use my referral link to sign up and we both will get $50 credit.