hot water from compost

Building the compost heap

With gas bills ever rising i have been looking at various ways i can reduce my bills, i have ruled out solar heating as i am on the ground floor of a converted victorian house. my back yard is small and gets less than 2 hours of sunlight per day.

I have known for a long time that compost heats up and have always thought how can i harvest the heat for some practical use.

my first attempt in january 2009 was a heap approximately 1m x 1m x 1m

I had placed 150m of garden hose though the heap and connected it to the outside cold tap with the garden hose connecter on the end.

i was pleasantly surprised to how quickly thew heap warmed up.

In 3 days the temperature had reach 60c

the water was far too hot to put my hand under it.

below is a temperature chart for how my heap warmed up

Air Compost date

temp temp ⁰C

3 3 9 Jan 2009

0 32 10 Jan 2009

3 42 11 Jan 2009

10 60 13 Jan 2009

4 59 14 Jan 2009

4 65 15 jan 2009

8 67 17 Jan 2009

5 62 18 Jan 2009

7 59 19 Jan 2009

7 56 20 Jan 2009

5 55 21 Jan 2009

10 55 22 Jan 2009

7 50 23 Jan 2009

8 45 24 Jan 2009

1 44 2 Feb 2009

2 36 5 Feb 2009

7 15 15 Feb 2009

my first attempt of collecting hot water from the compost has been a great success.

a few things i had overlooked

turning the compost heap is impossible with all the garden hose with in it.

i decided that i would leave the heap to rot down over the summer before attempting a new heap.