Windowfarms? And low tech alternative energy "Bio fuel"??

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Brian White
Windowfarms? And low tech alternative energy "Bio fuel"??

I found a bit about windowfarms about 6 months ago and had a small input about one of the toys I made.   It is an "opensource" hydroponic window garden? design experiment and it has gone worldwide. 

It started in Brooklyn

They now sell insanely priced kits in the USA so that people can do this themselves

However, I think it can be a really cool idea and should be expanded.  I think the concept could also be used to keep seedlings watered in an ordinary greenhouse with normal soil or seed starter too.

A lady in texas has used some of my old pulser pump stuff to design her much cheaper DIY system.

I also put on a video  to show that the airlift can be much much faster that what they show even with a cheap aquarium pump and much cheaper connections. (Perhaps you do not need fast water flow)

I was thinking about how this could be expanded to poor countries and did the "biopowered water pump".

(Not everybody has electricity!)   The biopowered pump just uses the gas produced from fermenting kitchen or garden waste or fermenting beer or wine to pump the water.  My first one (that did not make it to video) was powered by bakers yeast and a cup of sugar. The one I show was powered by ground up morning glory, potato skins, and moldy bread.

There are 2 videos for it

and (which is the same thing powered by an aquarium air pump.  This shows the fill and empty cycle pretty good.

Would anyone like to join in,

either doing windowfarms or in trying out the waste powered pump? Or expanding it to cover greenhouse "normal" plants. In parts of Africa, they use a high "spiral" garden to grow veg. It might be productive to have a "biopowered pump" circulating compost tea from bottom to top with that system.   It could be weed powered. 

The fermentation process probably kills the weed and its seeds.  

The bio powered pump is also on instructables at

It is community commons with commercial builds allowed. (Which means that you can market kits if you want). And charge insane prices too!



Brian White

Video of Britta  on Martha Stewart show showing the windowfarm concept.  They use an aquarium air pump (with a variable speed valve) to provide the air.  They have gone with a manufacturer who produce statewide.  They currently have some issues with that pump. 

It is important to be able to vary the speed or air in. Many aquarium air pumps do not have that facility but it is possible to add it.

Anyway, window farms are a go.Hopefully here too.




Love it! So far... will have to watch the whole thing, and all those related videos, when my reception is faster (like 4 am)

Unfortunately, i don't have any large windows that get enough sunlight, but may try this on our front porch next year, so i'll study up over the winter.

Two question for now:

The containers in the other video i started watching look fine for seedlings, but awfully small for mature plants. Will this be explained further on?

And is that your ultra-cool straw bale house?

Brian White

My straw bale house is actually a cob shed come greenhouse. There are many way nicer ones. Some really beautiful cob houses are on the gulf islands and there are tours of them every year.

The window farmers grow food hydroponically and i think the roots do not need so much room in that system. But really I do not know.

Window farms are all across the world now and  still in "open source" research mode.  but they have up to 17,000 participants! 

With open source research, I do something, and someone else takes it and makes it better, ( is a very good example) and she presents her experiments nicely and offers them back to other windowfarmers in a usable form.  This is exciting for me because in "real r and d"  everyone is too scared of everyone else to share anything!

"If I share, they might get the first patent and not me" which has a breaking and braking effect on progress.


Gulf islands.... sigh! Maybe someday we can travel again.

Thanks. I've been able to see a couple more of the short presentations, and it looks terrific. I've been saying for years that all those bloody great office buildings, currently wasted on money-pushers, would make good hydroponic farms. Acres and acres of window.

I hope the technology stays in the public domain long enough that nobody can patent and cash in. This isn't the kind of thing big business should be in charge of. This is real hope, for after.

Brian White

I am doing a bunch of short crappy videos to explain airlift pumps to people in the windowfarm project.

Many people cannot get the airlift to work reliably.

I am mostly doing demos of the T-Joint method but there will be a bit of more complicated stuff too.

Basically I know quite a bit about it after all the pulser pump stuff that I did over the years.  When they are all done, I will edit them into one decent one and take the short ones offline.

Their community site (for the DIY people)  is at 

There are several Canadians in the project. One person has adapted my dripper tracker idea (for solar cookers) to control the drip in their windowfarm. I believe someone is working on converting the clock based tracker for windowfarms too.   (The little aquarium pumps are noisy and people want quiet methods).

I have not done a windowfarm myself and I might never get round to doing one. is my youtube channel and there is windowfarm stuff in recent videos and I have a playlist called windowfarm research too.





A while back you asked how one could regulate the use of a battery, so that it would not totally discharge.

Are you familiar with a reed switch? It is a switch that closes in a magnetic field. Usually the contacts are enclosed in a small sealed glass tube, with some copper wire wound around the glass tube that created the magnetic field to close the switch.

Since the strength of the magnetic field depends on the current flowing through the windings you could probably use it to cut off the current to your airpump as the voltage in your battery drops below the point of your choise. I have never used a reed switch for that purpose, but cannot see why it could not work. The mainthing is to get a reedswich that can handle the load of your pump arrangement, and to keep the switches power consumption to a minimum.

Brian White

Thanks, Bubbles, sounds like a good idea. I will pass it on to the windowfarms people. Some of them are keen on solar powered windowfarms too and the same problem applies to them.  I got an inverter in Can Tire yesterday and it has automatic shut off. I open up the packaging and no info on what the cut out voltage is.  Such an important thing too! In xscargo there is a duracell one and it has a cut out of 10.5 volts if I remember correctly. I checked in some forums and they say that such a cut out voltage will quickly kill a 12 volt lead acid battery.  2 or 3 discharges to that level and it greatly reduces its capacity.

So I am not too impressed with the consumer eletronics sector right now.


Another thing to keep in mind, when selecting a reed switch, is that the switch should have some hysteresis to avoid the switch from hunting on and off. It would be nice to have a three or four volt difference between it opening and closing. Then for example the switch would open at 8 volt, stopping the pump, and close again at 11  or 12 volt restarting the pump when the battery has recharged to that point.

Brian White

A friend on youtube who does windowfarm stuff  saw my latest pulser pump video and suggested a "pulser pump nano".  A tiny version. People have always been put off from making a pulser pump because you have to dig a deep hole beside a stream or river to make one.  I don't have  a stream to play in anymore but I was able to try the airlift section of the "nano" today.  I tried 2 different pipe sizes and the smaller one (the blue tube in the video) was not a success.

However, the second size was very good.  Using the tiny air pump for an aquarium, and the  T-joint method with 22 inches of submergence, I was able to pump water 13 ft high today. And it looks to me as if I could pump way higher.  This means that a pulser pump with a tromp section about 3 ft deep and a bundle of these little tubes for the airlift section, could do some serious pumping.

In the windowfarms community,  I think it is settling the arguement about how best to produce airlift. The T-Joint is winning.


Brian White

Windowfarms is having a kickstarter event at

I am an active part of the "community"   and I am very happy that they decided to go with the "T-Joint method" (the airlift method that I pushed and demonstrated in videos)  as part of the commercial kit that they are selling in the kickstarter campaign. I am involved with several other open source "hardware" groups and this is the one that listens most to users, takes their feedback  and encourages them to collaborate in a proactive and meaningful way. Now it is clear that they use what we have done to improve their product too! It is GReat! Kickstarter figures as of now are below.:


pledged of $50,000 goal

days to go

Brian White

Today they have reached their $50, 000 goal. Well done Britta!


Brian White

I have a few days between work projects so here is a post showing how to use a cheap 1 outlet aquarium pump to power 2 or 3 airlift columns. (If you imagine 4 plants per column, it means you can grow 12 plants (instead of just 4 using the crappy pump to run one column).  (I think windowfarm kits sell with a 4 outlet pump but they are much more expensive) than the "normal" ones.

So, nothing too special here, just a demo that this can be done. I did this because someone mentioned that they couldn't get their second column to work. (And it was really hard to help them because they didn't post video). It is easier to figure out what went wrong when you experiment.