I've been playing around with applying aquaponics to the windowfarm idea (bunch of recycled water bottles and net pots in a city window). Here's a youtube video from the summer when things were working.
The problem with the windowfarms is they aren't much more than edible decoration - quantity is too small to actually live off. And for me, doing aquaponics, clogged pipes mean worry about fishes and plants.
I wanted to scale up, but I'm constrained to a windowless room. And I'm on a budget.
I've started up a blog at 3x5aquaponics.blogspot.com to talk about what I'm doing. My aim is to create a "nice looking" system that can be had for well under $1000, lights and fish included. Ultimately I expect to be able to fit 5 of these systems (or at least 5 growbeds) into my windowless room (the green bits in the layout below show a closet door and a large storage unit I'm hoping to clear out over time).
PS - I was surprised to see the pump I'm using (Pondmaster 140 gph) only consumes 10 watts. And the Tetra Whisper 100 only consumes 4.8 watts. That's nutty small. The lights will end up consuming 216 watts per growbed (using 4 T5 bulbs), but I project to spend less than $80 a year for electricity at this rate (calculated for a 3 growbed footprint).
Only $80 a year to support the lighting for the system, your electricity there must be pretty cheap. All five lights on together is over a kilowatt and each kilowatt hour here costs more than 10 cents each. So at my electric rates just running that many lights for 16 hours a day would be over $630 a year. Oh but wait, you said for 3 beds, that would still be over $378 at my electricity rates.
I'm guessing your projection of less than $80 is per month?
Here's what my electricity rates are:
First 800 kWh @ 2.233¢ per kWh
Over 800 kWh @ 1.260¢ per kWh
Let me go off and review my math, but in any case, my costs are very different from what you would expect, if you are paying $0.10 per kWh.
I'm putting aside some time this weekend to construct a second GB for my system, and your post helped clarify a few things. Linking to Affnan's video really helped. Thanks!
Just thought I'd update this discussion to mention that I figured out how to make an inexpensive greenhouse and I figured out fish I could keep outside (bluegill), so I've created a 40 sqft growbed system in my backyard. I've been blogging about it over at 3x5aquaponics.blogspot.com.
To review my electricity usage, now that I'm outside, I've got two Tetra air pumps (10 watts per hour for 240 watts per day) and a 1000 gph HydroFarm Active Aqua pump (99 watts per hour running 16 hours per day for 1600 watts per day). So that rounds up to 2 kWh per day or $0.025 (@ 1.260¢ per kWh). That's less than $10 per year. Even for you folks who pay a dime per kWh, that'd only be $100 per year. Not to mention that 2 kWh per day is within spitting distance of what you could expect out of a modest solar kit, for someone who wanted to get off the grid.
I'm using garden hose to carry water from my pump to the growbeds, which makes the cost of that part of the system quite affordable.
I estimate total cost for the 40 sqft growbed system, including greenhouse, fish, and media, at under $1200, assuming one goes for inexpensive (e.g., growing own plants from seeds versus getting semi-mature plants from nurseries, locally sourced river stones versus S&H and cost for expanded shale or hydroton):
Rubbermaid stock tanks - $480
Cinderblocks & planks - $60
Pump, hose, & fittings - $140
4 Bell siphons - $40
CHOP plumbing - $15
Air Pumps, tubing, & air stones - $60
Media - $50 to $500 (depending on type and if available locally).
Fish - $40 (50 bluegill for ~$0.60 each [3-5" size])
Seeds - $10
Extras (Seasol/Maxicrop, ammonia, water test kit, pH up and/or down) - $100
8 ft. x 12 ft. Greenhouse - $200