Does this save money ?

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bobukbrewer

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I usually use 32 litres of tap water to make 22 litres of beer after mashing and boiling. Next time I will start with just 20litres of water but keep all ingredients as before. Then dilute at bottling stage to get 22 litres. Should save on electricity as less to heat up to 70 C for mash and less to boil. Maybe add extra hops to allow for lower utilisation due to higher OG. comments please.
 
There's a calculator for doing this on Brewer's Friend, I do it all the time as my BIAB setup is quite small so I do a reduced-volume mash and boil, and top up afterwards. I guess it saves electricity too.
 
If I'd about to liquor down the wort I'd boil the tap water anyways before it's going to the fermenter.
 
Brewing a 60L batch uses around 6KW, system efficiencies dependent. Water is cheap from the tap but hops are expensive in comparison, I can't see how you will save money when you sub an expensive ingredient to try and save money on energy? More energy is utilised in fridge cooling over time for the same batch of beer (assuming fridge storage of bottles).

I would say no, you won't save money - swings and roundabouts!
 
Also be aware that if you're doing a large post boil dilution then the beer will not taste the same as if you'd made it 'properly'.
I normally do 18L brews in a 30L boiler. One time I doubled up on ingredients then diluted afterwards to 2 X 18L lots. The beer, a brown ale, was ok but definitely didn't taste the same as it did normally. Mashing works differently at higher concentrations, also hop utilisation.
 
Stan - I am not going to add a lot of extra hops.
Cwrw - I am allowing for hop utilisation. And you could say I was mashing to make a 7.5% beer - is that really different to mashing to make a 3.8% beer ?
 
Stan - I am not going to add a lot of extra hops.
Cwrw - I am allowing for hop utilisation. And you could say I was mashing to make a 7.5% beer - is that really different to mashing to make a 3.8% beer ?

I'm with Stan and Cwrw666 on this.

The tiny amount you'd save (we're talking pence rather than pounds) by heating/boiling 20L of water instead of 22L would be mostly offset by the extra hop usage.

The thickness of the mash (malt to water ratio) definitely has an impact on the final outcome of the beer, particularly in terms of efficiency and the fermentability of the wort as it impacts enzyme activity.
 
Stu - see post 1 - 32 litres
Apologies, mis-read but my comment still stands, I really don't think you'll see a massive cost saving from dropping to that volume of water.

I estimate I use 13kWh of electricity to brew a 20L batch of beer, for which I start with around 31L of water. That costs me a total of £4.29 (33p per kWh).

Even if your electricity usage dropped linearly with the amount of water you use (which it doesn't) than going from 32L to 20L would save about a third, so £1.43.

I think in reality you'd be lucky to save £1 in total.
 
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wot Stu says - and doing a quick bit of tweaking of my last IPA AG beer in brewersfriend, to alter the hop and grain bill to make up for the different utilisation and mash efficencies between my 15l batches and back liquoring to 21l would cost about £1 more in ingredients

I have done this a few times, but really infrequently and its just not worth doing imho
 
The specific heat capacity of water is approx 4.2 J / g.K

ie, it takes 4.2 joules to raise a gram of water by a degree.

So it'll take 4.2 x 12,000 x 80 to raise 12L (12,000g) of water by 80 degrees (20° to boiling) = 4,032,000J, ie 4MJ, ie 1.12 kWh.

Current price of electricity is 52p / kWh

Which is a saving of 58p

The boil is unaffected as it's the same power for the same amount of time.

You'll probably spend more on the hops.
 
I usually use 32 litres of tap water to make 22 litres of beer after mashing and boiling. Next time I will start with just 20litres of water but keep all ingredients as before. Then dilute at bottling stage to get 22 litres. Should save on electricity as less to heat up to 70 C for mash and less to boil. Maybe add extra hops to allow for lower utilisation due to higher OG. comments please.
Check out this week's video from David heath.
 
Check out this week's video from David heath.

Good breakdown, homebrewing is still vastly more economical compared to shop bought, capital equipment costs excluded of course as that is highly variable, but there is usually a break even point when equipment costs are included (break even seems to coincide with a large equipment upgrade in my case, so I never really reach that break even point, even though I tell SWMBO it's the last upgrade that will last until my demise 🤣).

Interesting comment about the thermo electrical products being electricity hogs, slightly off-topic, but does that include items like air source heat pumps that some people have converted to? Given they are not as effective as gas heating have those that have converted to this type of home heating been hit with a double-whammy - less heating and more electricity cost (I won't mention the 24/7/365 noise of these units either, making it a triple whammy that also affects the neighbourhood).
 
The heat pumps they kept pushing only made sense if you were electric only, oil or lpg.
We looked at them pre covid as we are all electric & given it's a air/ground to water system & we had storage heaters, the cost was way too high even with government subsidy & they said our water pressure was too low.

In the end we went for air conditioning which is an air-air heat pump & kept the storage heater as a backup in case we get a really cold spell, or we need the heat storage due to being bombed back to the '70s.
So far air conditioner switched to heat is reasonable cost, but it is quite mild & this could just be due to better control than the storage heater.
 

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