Carbon footprint reduced with biodigester
On a small patch of land, Malachi Symonds has an orchard bursting with fruit.
One citrus tree alone carries more than 150 lemons.
His secret is a fertiliser he makes with his new biodigester, a machine that uses organic material to create cooking fuel and fertiliser.
The Green Business Bureau says that the machine is a system that biologically digests organic material, either anaerobic (without oxygen ) or aerobically (with oxygen).
Most food, including fat, greases and even animal manure, can be processed in the machine. Microbes and other bacteria break down the organic materials.
Mr Symonds’ company, Sunnyside Sustainability, is gearing up to sell the machines and other sustainability products such as methane-powered cooking stoves.
“I first saw machines like this while at Earth University in Costa Rica,” Mr Symonds said. “I thought Bermuda could really use something like this. Sewage is a problem in Bermuda. How do we get rid of it?”
His machine puts the waste to work.
Mr Symonds tweaked an existing prototype and ordered his own version from China. The biodigester now sits in his backyard, and for $8,000 including shipping and installation, you can have one too.
The biodigester is inspired by the digestive system of a cow.
“It works almost like an intestine,” Mr Symonds said.
The first step is cultivating bacteria that grows in cow dung.
“It is not easy,” he said. “You have to do it slowly. It normally takes about 30 to 60 days for you to adapt them to greens from the house, or whatever other organic material you want to put in there.”
Once the bacterial colony is going strong, the customer just has to feed the machine with grass cuttings or vegetable remains.
“It just has to be organic waste,” Mr Symonds said.
The biodigester is basically a high-tech composter.
Over time a nutrient-dense, but bacteria-free, slurry builds up in the tank. This can be emptied out through taps in the machine. Every few weeks, Mr Symonds collects the slurry, mixes it with water and feeds it to his plants.
If a customer is squeamish about slurry, he can handle that aspect for them.
As it is percolating, the biodigester can produce from five to seven hours of cooking gas a day. Most propane gas stoves in Bermuda are not really designed to go with the biodigester, but Mr Symonds is working on bringing in stoves that will work with them.
He said that gas from the biodigester smells similar to propane.
“It is like propane in that if you leave it running you will smell it, but otherwise it burns off,” he said. “This particular machine is adapted to Bermuda. It has a pressure gauge. It has a carbon filter. It has a water filter. It is basically filtering any harmful things you do not want to be burning in your house.”
The pressure gauge is to regulate a steady flow of gas from the pump to the stove.
Mr Symonds said the biodigester is a safe system.
“The biggest thing with propane is the pressure,” he said. “If you are thinking about PSI you have six months of gas in that tank outside your house. With the biodigester you have a few hours. And the methane gas in it is not pressurised.”
His target customers are people who want to have their own sustainable house or garden. To install the biodigester people need a space that is 5ft by 5ft.
He said the resulting, rich fertiliser could see increased yields in the garden, thereby saving on grocery store costs.
Mr Symonds has spent the past six months streamlining the system. He is only now presenting it to the public.
“I guess I will find out if people are interested,” he said.
Mr Symonds also runs a popcorn business called Paddle Popped.
For more information call 400-5922 or e-mail paddle-popped@hotmail.com.