Right, feel free to rip this to pieces:
Ingredients for 20 litres
Malt say 6kg @ £2/kg = £12
Hops say 100g = £5
Yeast say 1 pack dry = £3
Water say 1p/10 litres â 40 litres for brewing, 20 for washing = 6p
Irish moss say 5p
Sanitiser say 5p
Caps â 40 @ 2p = 80p
Leccy - I'll assume 11 p/kWh
Boiler â electric 2.4 kW
40 litres/40 kg, heated from 10C to 100C, 90% efficiency
40 x 4.2 x (100-10) / 0.9= 16.8 MJ = 4.7 kWh or 52p
Heating - Aquarium heater - 50W
1 week on for 50% of time
50 x 24 x 7 / 2 = 4200 Wh or 4.2 kWh or 47p
Or cooling - Fridge â 200W with compressor on, 5 W on idle
1 week, compressor running for 10% of time
(0.1 x 200 + 0.9 x 5) x 24 x 7 = 3360 + 756 = 4116 kWh or 47p
That gives about £22 or £1.10/litre.
A fair price for a good quality beer in the supermarket is probably £1.50 a bottle or £3/litre.
I've probably spent £200 on equipment, so the break even point is:
3 - 1.1 = 1.9 £/litre saved by home brewing
200 (£spent) / 1.9 (£saved/litre) = 105 litres
Obviously it works out cheaper buying a big bag of malt/hops, re-using yeast for multiple batches, re-using sanitiser, brewing a low OG, DIY equipment building etc.
If I was to use the actual price per litre of good beer over here (£10/litre) I would have no problems justifying a proper shiny set-up...
:twisted: