# (Government/eu grant for) Boiler insulation ?



## jpaul__ (Feb 19, 2016)

I borrowed an electricity consumption meter from Maplin, and was surprised to see that with the machine on, for typically 1 hour (which I do twice a day) used 0.3KW/hr - a Bezzera bz02 1.3kw element.

[in comparison the washing machine used 0.3kw/hr on normal 30c cycle ]

0.3kw/hr = 258Kcal is enough energy to heat about 3.6l of water 30->100C ie 70c delta. in practice I have only pulled about 300g through the machine whose boiler normally contains about 1 litre.

So about 0.2kw/hr is conducted/lost to ambiant air

With boiler surface area (sides) of about 0.06m2 I estimated if I covered this with 9mm armaflex material a brand suggested elsewhere with conductivity 0.034 this would conduct about 15w/hr, [0.034*0.06*70/0.009]

so considering maybe 50w/hr lost through top/bottom of boiler could reduce Energy by 2/3 saving 120w or about 3p a day based on 2hour use , about £10/yr electricity.

Enough foam costs about £10

I should maybe be more disciplined about turning the machine on and off when I want to use it, rather than turning it on for the evening and sometimes then forgetting until late, so some kind of auto-off timer might also be a good idea .

I think newer Silvia's do have an auto-off (CE rules ?) but nonetheless other than specifying element power I do not know if manufacturers make any concession to show running costs

(OK the machine will keep the kitchen warm in winter as a side-benefit)

*addendum*: maybe inlet water temp is more like 15c and boiler 120c so delta of 105c


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## Daren (Jan 16, 2012)

My head hurts. I'd happily pay the £10 so my head didn't hurt thinking about this type of stuff


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