Undersoil heating by greywater in winter?

I hope I am not being carried away too much in my interest in permaculture. Here's an open ideas to throw out.

We live in a pretty cold part of Germany near the Alps where winter it can on occasion get down to minus 20. Now I am interested in growing food using hotbeds and may try it this winter but the thought just occurred, if one had a greywater system is it not possible to use the hot water from washing machines or dishwashers to keep the soil just above freezing to grow crops?

I believe my temperature regime is similar to upland parts of say Oregon or -New York State.

My neighbor places container plants, roses in his case, over his septic tank in the winter to prevent the roots from freezing.  In our area, High Cascades of Oregon, if you were to leave the plants out without the warmth from the septic tank or inside a green house they would freeze and die. So I don't think it is a bad idea.
Robert

I think that if folks wanna use greywater all year, a greenhouse really needs to be involved.

paul wheaton wrote:
I think that if folks wanna use greywater all year, a greenhouse really needs to be involved.

Could you please elaborate on this?  Is there a graywater thread I am missing? 

I dont' know if it would work in such cold but I think it is worth a shot. does your greywater system  go into a tank? if you placed a bed on top of the tank and maybe even went so far as to line the bed with an extra insulative material it could give you just enough heat to keep cool weather crops going through the winter. I say go for it! and report back as to the results.

listenstohorses wrote:
Could you please elaborate on this?  Is there a graywater thread I am missing? 

Just my obnoxious opinion.  Although I think the graywater book mentions this too.

Your graywater contains teeny tiny bits of poop (washing your butt in the shower, etc.) and maybe you put your pee into this system .... so you want that sort of thing to get into a plant (or some microbial) instead of heading to your water supply.  In the winter, plants and microbials are almost completely dormant!  Unless, of course, they are in a greenhouse.  And you are right - some shower water really does a lot to warm a greenhouse.

 

In warmer climates, a deep mulch bed will remain microbially active year 'round.

polyparadigm wrote:
In warmer climates, a deep mulch bed will remain microbially active year 'round.

YES!!!

Which is exactly why I like the idea of building soil in cooler climates more than warmer climates.

This is a strange forum. Does rogertheshrubber think grey water is what goes down the sewage pipe? I think its the water from the shower and dishes but not from the WC. As grey water is mostly just water it couldn't heat anything like decomposing manure can, much as water reduces fluctuations in temperature, if you store quantities of of it, because it lets off any heat it has retained a good deal slower than air does though the bath water seems to cool down fairly quickly, it does not actually heat places.  I have read about putting tanks of water or swimming pools in to green houses to reduce sudden changes of temperature because water to some extent holds heat, in various places, apart from on the site of Larry Hartweg, before i read his site, in two architectural magazines, so that as information it used to suprise me but as i came across it more often, i started to just accept it. agri rose macaskie.

rose - I think the heat would be primarily from the hot water used in the household. some households with wash machines, dishwashers, mulitple family members taking showers etc....can send alot of hot water down the drain. it certainly wouln'd generate heat the way compost would but daily shots of hot water could assist in warming the soil to a slight extent and in some areas just a few degrees could make a big difference.

  Had not thought of the few degerees extra heat from hot water . Thinking of the importance of a few degrees in some places or situations is interesting. agri rose macaskie.

Suppose you have four people in your house that take showers averaging five minutes.  20 minutes of showering at three gallons per minute makes for 60 gallons of very warm water. 

Put 60 gallons of very warm water in a 60 gallon bucket in your living room and I think you might have a lot of heat for the day. 

It takes a lot of power to heat water.  And, once heated, water holds a lot of heat.  If the water is 104 degrees and your optimal room temp is 70 .... I think there can be a lot of advantage to getting that heat out before it goes away.

Ok so something like putting the septic farther from house and letting hot water go thru pipes under garden?

thats an interesting idea. I my first thought though is that that hot water traveling through long pipes is going to cool rapidly. it would act as a radiator. It seems alot of the usefullness might come from a largeish amount of hot water standing and slowly releasing heat over a period of time.

I wonder if a prart of the trick could be in the fact that if the temperature differential is high then the water loose heat quickly and if its low the loss is slow, maybe it is when the temperature differetian between the water an dthe air is low ther isnot much ¡ difference, nthat having a body of water stops fluxations in temperature where there is water.  This summer , If I ran a bath and forgot it, in the hot weather, it was still hot ages later, the moment weather got less hot my forgotten baths cooled really quickly.  Maybe it is in  circumstances of small temperature differentials when water cools or heats slower that bodies of water can make a difference.
  In green houses those who metion the use of oil drums full of water to stead the tempreature, talk of putting a line of oil drums full of water to pick up heat during the day and let it off at night, so stabilising the heat in the green houses, that is if you aren't rich enough to put in a swimming pool, a really big body of water. An oil drum is a fair sized, so a row of oil drums would be like like several baths so it would have a bigger effect than one bath, the water is warmed by the heat when the sun shines on the greenohouse.
  Permaculturists say or some of them do, i believe, "right we aren't rich but we can organise a lot of people and so build you a swimming pool without too much trouble".
      Just turning over the ideas that occur to me. It is a person who really understand that could cross the T's and dot the I's on all this.
  i know that, in painting, being precise, a few degrees, can make a big difference and on other occasions you can paint loosely and  no one will notice, it wont matter in that spot. agri rose macaskie