StoveTec’s Hot Rocket Stoves

StoveTec’s wood burning rocket stove on the left, charcoal and wood on the right.

A reader comment alerted me to a very cool product, the StoveTec Rocket Stove, offered by the “not-just-for-profit” wing of the Aprovecho Research Center. Profits from sales of the stoves benefit the Center’s research. StoveTec sells two rocket stoves, one for wood and the other for both wood and charcoal. While I haven’t tested one, the $37 to $40 price is a bargain.

Rocket stoves are a simple “appropriate” technology that burns small pieces of wood and charcoal efficiently. We’ve blogged about them before and even constructed our own out of a vent pipe and bricks. Instead of burning a log to cook you can use trimmings from trees, bushes and even agricultural waste. According to StoveTec,

“StoveTec Stoves, rocket stoves invented by Dr. Larry Winiarski, use 40-50% less fuel and reduce emissions by 40-75% while reducing green house gas (GHG) emissions an estimated 60% or 1-2 tons per year. These stoves are preferred over other improved cook stove and three stone fires by 95% of users in Uganda. High adoption and preference reported in India, South Africa, Ethiopia and Chile proves the stoves great versatility among many different users.”

Looks like they could find a nice home in North American as well. Do some pruning and then cook dinner. How about a rocket stove tailgate party?

Going Gray!



Got a nice note and some pics from Ben in Portland:

“I bought your book and it has become my mission manual. We own a house in Portland, OR, and I just today did my first project out of the book – routing the shower drain into the garden. It cost about $60 for all the pipe, glue, a 2” hole saw to drill through the wall, and a new drain kit (my old drain was decroded as crap). Our house is only 750 sq. ft. (plenty for me, my gf, and our 3 dogs), and luckily our bathroom is right next to the garden plot I’ve had for about 3 years now. We’ve got a ton of squash going, which as you know takes a good bit of water, so I thought our not-so-gray shower water would be much appreciated by the little yellow bastards. Another benefit is that we won’t have to deal with the recurring shower clogs which have been forcing us to use drano.

The drain setup was super simple from a plumbing perspective, so all I did was cut off the old drainpipe, replace the drain assembly, and route a new pipe out to the garden. It took three 22 degree couplers, one 4 foot and one 10 foot section of pipe. the pictures sort of show what the finished piping looks like. I know it looks like I had to rip through the floor to get to the drain, but that’s just because whoever installed our shower years ago did a terrible job.

I drilled holes every 6 inches or so in the pipe that goes out into the garden. I may need to cover them with mesh (I’d appreciate your advice here) and dig some trenches to route the water into the rest of the garden, but for now it’s working great!

Thanks for your wonderful book and website. I will send you more pictures as i do more projects!

-Ben”

California’s New Greywater Code: Common Sense Legalized!

On the left is our yard which is irrigated by the washing machine. On the right, the neighbor’s yard which is never watered.

This Tuesday the California Building Standards Commission legalized our formally outlaw greywater system. For several years now, we’ve sent our washing machine waste water out to fruit trees in the front yard. The new regulations are a rare common sense moment for our otherwise troubled state government. Let’s hope our current hard times spur more innovation like this. Originally slated to go into effect in 2010, the plumbing code was updated as an emergency measure to deal with drought conditions that have plagued the southwestern US for years. Under the new California greywater code:

1. In most cases you won’t need a permit.

2. Allows discharge into a simple mulch basin rather than the expensive and complicated sub-surface emitters required under the old regulations.

3. No exspensive pumps or filters required!

Here’s the new code as amended (pdf).

Unfortunately the code can be superseded by local municipalities. Plumbers unions opposed loosening the code, no doubt fearing the loss of business. Combined with NIMBYs, they could put pressure on city governments to keep greywater illegal. It’s time for us Californians to be vigilant and start letter campaigns should cities try to restrict our new right to use our greywater.

As for the practical side of this new law, I’d suggest that anyone interested in installing a greywater system keep it simple and low cost. I can’t think of any better resource than Art Ludwig’s book The New Create an Oasis with Greywater: Choosing, Building and Using Greywater Systems and his website oasisdesign.net. Take note of Ludwig’s free open-source laundry to landscape plan.

And don’t forget, Homegrown Evolution is offering a DIY Greywater class on Sunday August 16th at 11 a.m. in Silver Lake (Los Angeles). Sign up here.

The Great Greywater Debate- PVC or Polyethylene?

PVC v. Polyethylene

Homegrown Neighbor here. I’ve been wanting a greywater system for a long time. My old house does not exactly make access to the pipes easy, so I’m starting with just the washing machine. The neighbor, Mr. Homegrown, is anxious to try out a new design from Oasis.

So we have been trying to get all the pieces and get it done- and here is where we get stuck. The system can either use polyethylene tubing or pvc. PVC is ubiquitous, cheap and toxic. Just how toxic, I don’t know exactly, but I’ve never chewed on any pieces just to be on the safe side. PVC is toxic to manufacture as well. This makes polyethylene the more ecological approach. But it is very hard to find in the size we need for the greywater system. And you have to buy a minimum amount- about 250 feet is the smallest we have found so far. For my yard, we probably only need about 40 feet. Plus, you have to mail order it. If we go the pvc route, it would cost far less and we could buy all the pieces at the local hardware store. We also want the system to be replicable so that we can share it with others and encourage them to use greywater. Searching for the parts for the polyethylene version is confusing – pvc is easy and accessible. This is the challenge. So what do people think- should we go with pvc or polyethylene?

Mr. Homegrown here. So I just found a local source for 1-inch polyethylene: Aqua-Flo. Cost is in the neighborhood of 33ยข a foot depending on how much you get. It comes in 20 foot and 100 foot lengths. So I think we’re gonna go with polyethylene. Incidentally, when I called Aqua-Flo they asked if I was going to make hula hoops.


A correction and update 7/25/09: The Aqua-Flo branch I went to does not have black 1-inch HDPE tubing in stock. Other branches have it, but only in 500 foot rolls that cost over $300. A roll that long would make sense for a contractor, but for DIY greywater installations it ain’t practical. Aqua-Flo does carry a new HDPE product called Blu-lock. You can get 1-inch Blu-lock in-100 foot rolls for a reasonable price (more info to follow in another post). Blu-lock uses special proprietary fittings that are easier to assemble than conventional mainline drip tubing and, intriguingly, allow for disassembly. I’m going to test Blu-lock and will report back on the results.