Ideally it’d be done with re-used materials, like the second guy who used old insulation from an RV.
But at least in my area from a local hardware store, I can buy 1 1/2 inch 4x8ft sheets of expanded polystyrene insulation for $20 per sheet. 3 sheets should be enough for most fridges (or 4, if the heat exchanger is underneath the fridge), so 60 to $80 for new materials.
Using this energy star savings calculator, it spits out this rough estimate of the yearly cost of a 1990’s fridge:
If the foam decreases energy usage by 50%, that would mean a $115 savings within the first year, paying off the initial foam costs within 6 months of use.
According to that same calculator, this is the numbers they give regarding carbon emissions compared to using a new energy efficient fridge:
It’s difficult to find the information of expanded polystyrene’s carbon footprint, I think I found it here? Specifically this chart from that article:
The second column there can be ignored, since we’re not trying to achieve R28, which since XPS foam is pretty low R value compared to other foam insulators would take a LOT of foam. So I guess the first column is the relevant one.
RagnarokOnline@programming.dev 5 weeks ago
Holy shit this is some #theydidthemath stuff.
6 months at paying full price for the foam is a ridiculously quick turnaround given the lifespan of a fridge (easily 5 years). Plus, you can probably reuse the prior fridge’s foam on the next fridge, so that makes it even better.
Why don’t people do this more often? If the gap in my current “fridge space” wasn’t so small already, I’d be tempted to go find some foam.
averyminya@beehaw.org 5 weeks ago
I would guess that most people don’t know, and as mentioned it’s ugly and sadly it seems the majority of people care about aesthetics more than efficiency.
And also like you, I would do this but my fridge space is also definitely too small. I also think our fridge is new enough to be one of the metal dissipators
quicksand@lemmy.world 5 weeks ago
My only question is where is the outlet for the heat pump? If it goes out in the front then okay, but if it’s pumping out hot air into a now insulated area that might be a problem