Entering Items into the True Zero Spreadsheet using $ values

In the True Zero Spreadsheet "ELEC_PLUMB_CAB" tab entrants will find that there are some items that are entered using dollar values.  This occurs with appliances that are complicated and contain multiple materials and parts.  In such cases there are no or limited EPD or generic embodied carbon figures available, and the best data we have comes from Input-Output (IO) economic analysis.

IO analysis takes ABS data of the total greenhouse emissions of an industry sector and divides it by the total dollars of product produced by a sector.  This gives a figure of CO2/$ emissions. 

While this method produces a $ figure that captures all emission, it loses nuance of the differences in embodied carbon of different materials.  This price method also has the flaw that prices tend to rise and fall with supply and demand, while actual embodied carbon of any one product should stay consistent.  For both these reasons the IO dollar method is only used in this section when other data is not available. 

So here are the rules when using the dollar method:

1. Don't include labour.  Only enter the unit price of the appliance.  Where all you can find are supply & install prices, minus 30% to remove the labour.
2. Don't include gst.
3. Where a range of prices for a product type exist, use the average price of the cheaper version of the product.  Usually the price difference is due to quality, rather than factors that would add embodied carbon