Thoughts on this earth sheltered greenhouse for an aquaponics system?

Ola! Posted this over at the wofati sub forum, thought I'd stick it over here too for more of an aquaponic perspective

Planning to start up an aquaponic tower system in the north of England, figuring out with what kind of shelter to house it in. I plan on putting together a tower system; seems to fit quite nicely in a Oehler style greenhouse.

Still searching for a site so the angles of the panes aren't set in place, it will probably be erected on a flat site.

Our fishies will be in IBCs which are placed in where the cold sink would be. As our towers are raised off the ground and we might incorporate some form of heating in the future I'm not that worried about frost.












Any thoughts on this design would be very much appreciated! Would be great to hear from people who have had success using tower systems.

Sean

I'm about 4-5 feet deep into this exact project right now. I was digging it by hand before the ground froze (Northern Michigan (USA)), but I'll pick back up once spring rolls around. Our designs are pretty similar, except mine is only illustrated on the pages of my mind. I've encountered pooling water, which was mildly surprising (hilltop living, basement is woodframed with no problems....), but I'm guessing the 150% of normal precipitation levels might have had a hand in that. I'll be piping the excess water to a lower aquaculture site. I've sorted the excavated soil as I've worked - top soil for other projects, clay for other projects, mixed clay/sand/gravel I used to make a sledding hill for my youngins. I have no regrets about choosing to dig by hand. It was great exercise for me, and I learned a lot about the soil in that area. Best of luck. I keep waiting for people to tell me I'm stupid, but people seem to be waiting to see how it turns out.

Wondering if you have had a chance to look at Michael Reynold's Earthship concept. Recycled tires rammed with earth might make a good thermal mass for the greenhouse, eliminate the timber dilemma and re-purpose some waste. This is a great idea, ICF are perfect for insulated tanks. Look forward to seeing your finished product.

Matt Rainey wrote:I'm about 4-5 feet deep into this exact project right now. I was digging it by hand before the ground froze (Northern Michigan (USA)), but I'll pick back up once spring rolls around. Our designs are pretty similar, except mine is only illustrated on the pages of my mind. I've encountered pooling water, which was mildly surprising (hilltop living, basement is woodframed with no problems....), but I'm guessing the 150% of normal precipitation levels might have had a hand in that. I'll be piping the excess water to a lower aquaculture site. I've sorted the excavated soil as I've worked - top soil for other projects, clay for other projects, mixed clay/sand/gravel I used to make a sledding hill for my youngins. I have no regrets about choosing to dig by hand. It was great exercise for me, and I learned a lot about the soil in that area. Best of luck. I keep waiting for people to tell me I'm stupid, but people seem to be waiting to see how it turns out.

You seem to be a few steps ahead of us Matt, hope things are thawing out over there! Still searching for a suitable site, may have to come up with an above ground design...

Would love to see some pictures of your progress, we're gonna try and dig it out by hand too

dave dixon wrote:Wondering if you have had a chance to look at Michael Reynold's Earthship concept. Recycled tires rammed with earth might make a good thermal mass for the greenhouse, eliminate the timber dilemma and re-purpose some waste. This is a great idea, ICF are perfect for insulated tanks. Look forward to seeing your finished product.

Thanks for the suggestiong Dave! I've seen a few films on Earthships; they're very impressive. Struggling to find a site where I can sink the greenhouse into the ground so perhaps a rammed earth tire construction could be the answer! What are ICF, pardon my ignorance?

Insulated Concrete Forms are snap and stack forms for poured concrete walls. The nylon or plastic spacers can be used as screwing "targets" for sheet goods like cement board, plywood or drywall. Lined with EPDM pond liner you end up with a strong R45 fish tank. I think it is usually easier to build a berm than find a suitable hill that may contain something unwanted. Your mass can be shaped to drain and added insulation barrier can stabilize temperature even further.

dave dixon wrote:Insulated Concrete Forms are snap and stack forms for poured concrete walls. The nylon or plastic spacers can be used as screwing "targets" for sheet goods like cement board, plywood or drywall. Lined with EPDM pond liner you end up with a strong R45 fish tank. I think it is usually easier to build a berm than find a suitable hill that may contain something unwanted. Your mass can be shaped to drain and added insulation barrier can stabilize temperature even further.

That's great Dave, thanks for pointing me in this direction. I'm starting to think that building a berm may be the way, or maybe opting for something straw bale perhaps. Thanks again!

Hi Sean,

I'm jealous - it looks awesome!

One thing about thermal mass storage is that you need to have it contained inside your greenhouse in some way. So, for example, you could put some straw bales behind the earthen part. Then you would roof in the rest of the earth so the heat would be stored rather than transferring to the rest of the dirt or outside air. The Chinese build these kinds of greenhouses.

A way to store even more mass is to use black metal barrels full of water. They tend to stay above 32 degrees F because of freezing, so they can help keep your greenhouse from freezing.

One common temptation in aquaponics is to build an awesome greenhouse, then have your whole system be basically exposed to the inside air. This is a big mistake. The most important layers of insulation and air sealing are over/around your tanks and grow beds. Much - perhaps most - of your heat loss comes through enthalpy losses, not just convection. Controlling these losses are crucial.

I wish you luck! Love to see how things progress.