Wednesday, October 12, 2011

Special Projects

Drifting from the buzzing metropolitan area of Boston to the woods of New Hampshire does not happen in one step, not for me anyway. As a mechanical engineering student at Northeastern University, I have been attempting to find that specific niche in an otherwise unspecific major. Mechanical engineering covers anything from aeronautics to solar power to prosthetic limbs. Luckily for me, I was able to spend time in a lab, at a desk, and now at a farm through Northeastern’s co-op program. The drastically different environments that I have been exposed to allow me to better understand what it is and what it isn’t that I want to do with my degree.

During my stay at D Acres I have been focusing on “Special Projects.” These deviate slightly from the day-to-day activities usually seen on the farm. The first special project was an anaerobic digester. It differs from compost in that it works without oxygen. The breakdown of oxen and pig manure in a water environment releases methane gas that can then be used for cooking or heating purposes. The project specifications can be found at The research involved was fairly intensive. A number of different designs exist and it was difficult to find one that was suitable to the New Hampshire climate. The final design was a combination of a few, but on a much smaller scale. The small scale gas production will only be suitable for demonstration purposes. I felt the design was fairly successful and saw methane production within the first week. After that week, however, the temperatures cooled and gas production decreased. To fix this, compost was piled around the digester which has been successful in raising the temperatures so far.

The remainder of my stay has focused on bicycle power. This subject has been studied by many different people in many different places around the globe. Having an avid interest in bicycles I was very excited to tackle a bicycle-powered project. That was 4 weeks ago. Since then, I have built a power take-off for an apple crusher, a direct-driven washing machine, and finally a portable power station. Each bicycle set up is a different approach to the same thing—bicycle power. The documentation is available at The power take-off combined with the portable frame (sections of an old bed frame bolted to the rear wheel of the bicycle to raise it off the ground) of the power station leaves the bicycle fully intact and allows the user to ride to where it is needed and then hooked up to the machine it is going to run. Practically anything that is belt-driven can be run by one of the setups. The portable power station with flywheel is great for keeping machines running smoothly.

All of the projects have had points that were challenging, frustrating, and rewarding. The most challenging aspect is the availability of resources and machining equipment. At previous internships I worked in shops backed by multi-million dollar companies. Fabricating only required an order to be placed for all the parts needed with very few cost restrictions. Everything at D Acres has been built with parts available on site. Some parts have been found in the resource pile, others in the eaves of the barn, and most of the time parts are pulled from beneath piles of other parts. Although it is challenging to locate parts needed for projects, making use of old parts is a great practice. It keeps my brain constantly forming alterations to a previous design—making the design work for the parts available. The philosophy yields minimal cost and negligible waste. No gas is wasted in the shipping of parts and parts that had no function become productive pieces of the D Acres community.

The most rewarding part of my stay has been being able to see people actively use the equipment. Members of the community really enjoy being able to crush apples by pedaling bicycles, children and adults alike. It also eases the workload of people at farm. Crushing apples used to take at least twice as long when doing by hand and required exerting much more physical effort. Now, a five-gallon bucket of apples takes less than three minutes to crush.

In coming weeks I will be pursuing powering items in the kitchen and solar-powered cookers. The food processor is used on a regular basis and being able to figure out how to power it without electricity would be a large achievement. Having more efficient cookers, such as a parabolic oven, would reduce cooking times in the sunnier months. Research and design is still necessary at this juncture, but I look forward to the challenges ahead.

-Joey Kile

1 comment:

Chris said...

It's so cool how there are blenders etc. that are bicycle powered now-a-days...I think the Shakers would be proud. I've often thought about looking into it even in my own house (though I'm not quite sure how I'd set it up). I have a folding bike that I would hook up to it though, and basically, I'd do my ride while making my recovery shake. Then, since I've got a folder, I'd be able to put my power source in the cupboard with the blender.