A Renewable Energy Adventure
After banging up thumb pretty good from too much chiseling… I decided it was time to switch to an approach for construction based upon layers. I could “mass” produce a consistent shape for each layer for a whole set of three blades and their would be more consistency and less work. I simply cut them with a table saw and finished off with a jig saw, easy-peasy.
So here is my first test of this strategy, just remember clamps, clamps, clamps, mixed with glue, glue, glue!
I’m starting a new 3 foot wooden blade to test out using a higher blade twist. This one should hypothetically have a 24 degree highest angle of attack for the airfoil at the base of the blade. The starting block of wood is constructed by gluing 2 2×8’s together and then I plan on chiseling and sanding it down to the correctly twisted airfoil. I think it will be easier in the future to start from a bunch of jig saw cut 1×8’s glued on top of each other so I have to chisel out less wood. I also plan on buying a draw knife tomorrow, which should make my work much easier as I try and build smarter blades quicker.
I started reading “Developing Wind Power Projects: Theory and Practice”by Tore Wizelius, yesterday on the train and it has done a quickly done a good job of educating me on wind power. As I read and work I have started keeping a little bit of a journal. In later days, I will probably scan some of these pages to show diagrams and such.
This book does a good job of making me think critically about design and has taught me important things like how the airfoil at the tip of the blade can be imperfect in order to increase the swept area of the turbine, because increasing the swept area is more important, as weight is the decisive factor in blade design.
I’m also starting to think critically about how to get an appropriate twist along with an appropriate combination of airfoils to vary the stall speeds along the blade and allow the blade to start up in lower winds and perform well in high winds, while keeping the nominal wind speed low. Testing will be required…
If you want a little bit more information on the type of turbine I am designing here it is: I am planning on finally building a ten foot diameter 3 bladed turbine that runs on a direct drive(meaning no gearbox) synchronous generator to a frequency converter to a transformer to a series of batteries probably. The rotor will be kept facing into the wind by a tail made of a welded metal frame a wood tail. I want to figure out some sort of system to remotely send information such as wind speeds and energy production either by text messages or have it all recorded on sight. The tower will be some sort of a guyed tower with a concrete base. I am also trying to design some sort of a remotely controlled mechanical break to stop the turbine in inclement weather or freeze it during repairs.
Here are some photos of the test blade I was constructing earlier tonight. As it got late I started to switch to hand tools because of noise issues. It would be more efficient to wait until tomorrow to do lots of the airfoil construction because I plan on buying a drawknife, but I really enjoy chiseling, so chisel I did.
It’s very relaxing working in the garage and it was nice to get to stand up for awhile, after spending much of the day sitting and scanning 4×5″ negatives for my photoblog. I listened to a lot of The Mountain Goats and a Leonard Cohen Best Of CD.
While I was in Rhode Island the past two days they bought an electric heater for the garage! too bad it was 60 today.
Clamps are very important. You can never have too many clamps.
Here is me working away!
The mallet on the left is Stephen’s homemade one, I decided to stop using it because I was afraid I would break it… so I switched to the one on the right.
Chiseling may be slow, but it is a great way to slow see and visualize the blade in the wood and you get to watch it emerge, in a way that a band saw can’t.
If anybody has any experiences building homemade fiberglass wind turbine blades off of a plaster mold, let me know, because I am soon embarking on that adventure!
Whalepower(it’s a wind turbine company, they don’t make power from whales)
Scoraig Wind(great details on homebrewed wind power)
Proven Energy a UK company with a really cool small wind turbine design.
Now I have big dreams of making a much large positive, then a negative out of plaster, then a bunch of positives out of fiberglass… High hopes, I know.
Our first turbine also now has a home and I guess that means I have my first customer. My Uncle and Aunt have a house up in the northern kingdom of Vermont and were interested in a small turbine to help supplement their energy needs and for emergency use in case of downed lines. So in four or five months, once the ground isn’t frozen, I’ll be able to put my first turbine in the ground.
As a Christmas present for Brittany Wright this year I decided I was going to aid her in the construction of a handmade wind turbine. She is a mechanical engineer with a focus on fluid dynamics and thermodynamics at Tufts University hoping to be a graduate student at The University of Edinburgh focusing on marine energy including offshore wind. She also took an advanced mechanical engineering class last semester at Tufts focusing on Wind Energy and I figured it was about time that she gets to build a turbine. I have a pretty functional machine and wood shop in my garage thanks to my brother Stephen MacLellan and my parents so getting started on blade construction wasn’t too hard, except for the fact that I had to quickly fully grasp the basics of visualizing a twisted airfoil in a 2×6.
Stephen was able to help me along and after visiting a few sites on the subject of handmade wind turbine blades, I got the idea. Some very helpful sites for me in the beginning were Hugh Piggot’s Scoraig Wind Energy, WindStuff.org, and the Renewable Energy UK Site. My first blade is really more of a test blade than anything useful and is a 24 inch blade made out of a 2×6 of pine. I plan on making two more anyways so I can build a small scale model including hub, generator and alternator as a base to build larger 6 or 10 foot turbines.
I’m an eighteen year old so I am still exceedingly optimistic and eager and as I was building the first blade I had the thought that I could make renewable energy my summer job and full time hobby. A quick glimpse at my Google Reader feeds reveals an obvious obsession with the environment, energy, and technology. For Christmas this year I even asked for a roll of flexible solar panels…
After a quick Google Chat with Brittany, I got her excited about the proposition and my mind started racing with ideas. Both of us know a good number of people without jobs in a pretty diverse range of fields so finding help shouldn’t be too hard.
Here’s my plan:
Brittany and me, Co-Presidents
Brittany in charge of Systems and Design
Ian in charge of Marketing and Ideas
Stephen in charge of Construction Division
L.A. Chief Financial Officer
Piers in charge of Sneakiness
Chris in charge of Accounting
Mike in charge of Legal issues
Matt general science help…
Stephen constructing our first test blades
