7 stars – Cost Benefit

ABCB and Tony Isaacs think this is a net benefit, tell me what you think? They actually say it has a negative NPV in Western Sydney but hey let’s do it anyway!

The CRIS or cost benefit used to make the decision on 7 stars suggests a large two storey house in Western Sydney will cost about $1,800 to achieve 7 stars and save about $180 a year! Pay back in 10 years.

Not sure what planet they are on!

Research & costings so far suggest;

  • The smallest single storey house will cost around $3,000 or so, perfect orientation/small windows
  • A typical North Kellyville house will be more like $15,000 to $30,000
  • Most project home builders are indicating $20-30,000 to achieve 7 stars
  • An architect designed house with large windows or your typical house with large windows to take advantage of the view will be more like $80-100,000 to achieve 7 stars

So you know who to call when it costs more than $1,800.

I am all for reducing carbon, working towards Net Zero, making progress, just think there is a better (more sensible) way to achieve this.

6 to 7 stars will save or potentially reduce your consumption by 300-900 kW PA which is about $70-200 Saving each year.

So, assuming energy costs stay about the same! It will take the following years to recoup your investment;

  • $1,800 / $180 = 10 years – unlikely
  • $3,000 / $70 = 42 years – unlikely
  • $20,000 / $200 = 100 years – most houses
  • $80,000 / $200 = 400 years – bespoke homes

Guess what, probably will get knocked down and rebuilt in around 40-50 years, so the savings won’t materialise. Even if energy prices rise it won’t stack up.

Most new homes have PV (solar panels to make energy) installed, it makes sense, relatively low cost compared to other items, the kicker for this argument, 1kW of PV in NSW will produce 1,400 kW PA and only cost $500-$1,000.

It will have a bigger net effect of reducing or offsetting consumption than going to 7 stars and cost a very small amount.

No, I don’t work for or sell PV.

Builders know what to sell, no vague guess until the design and energy rating is done.

Doesn’t mater if the home owner leaves a window or door open, still produces energy!

Pretty sure the Building Code says requirements should not go in the BCA if there are alternatives that produce better net benefits!

What did we get?

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