Daniel Lampie

The wind turbine is back up at RIT!  The turbine is now located on a small hill in a unobstructed area which should greatly help.  While the turbine was down, I completely rebuilt it and improved on some design elements.  The old turbine was built out of two pieces of wood, one for the generator and one for the tail, screwed together.  The two pieces could flex under stress, so I built the new turbine out of one piece of wood to prevent this from occurring.  I also sanded down many pieces of the tower as the sharp edges where rubbing against the wires connecting the turbine.

As I wrote earlier I replaced the blades as the old ones had a hard time spinning over 400RPM’s.  The new ones are designed to spin over 1000RPM’s and earlier tests show the new blades have greatly improved the performance.  I also replaced the batteries as the old ones where undersized for the turbine and only had a 14Ah capacity.  The new ones are Trojan T105’s and they provide a much larger 440Ah.

Today there was a good 15-20MPH wind in Rochester.  The turbine was working great and the amp meter was hoovering between 2-4A (24W to 48W), and would hit over 8A during a gust (96W).  Now it is time to hook up some gear for the turbine to power!

A solar hot water system was recently installed at my family’s house. The government incentives which accounts for about 30% of the system and the fact that the old hot water heater was broken were the main drivers of the project. The system is designed to provide hot water for four to six individuals which equates to 75 square feet of solar panels on the roof. We are using a dual tank solution since this is more efficient, but more expensive than just using a single tank. With the dual tank solution, one tank acts as a preheat tank which preheats the cold water from the street while the other tank is the hot water tank which keeps the water at a constant 120F. Since the water from the street is between 40-60F, a great deal of energy is required to heat this to 120F. n With the preheat tank, the solar panels heat the water from the street before it enters the hot water tank so less energy is needed to heat the water to 120F. The hot water tank has two backup sources in case the preheat tank is feeding water colder than 120F. During the winter the backup is a tankless coil in the boiler and during the summer it is electric which allows the boiler to be turned off.

We have only had a couple days of sun and the rest has been snowstorms. On a 30F sunny day, the preheat tank started at 58F in the morning and at the end of the day was 82F which isn’t bad considering it is 105 gallons (double the size of an average tank). The glycol (water freezes) which flows through the panels was a constant 140F which is incredible if you think of the low UV radiation that the sun produces during the winter months. Hopefully there will be a couple sunny days in a row to get the big preheat tank over 100F.

85 Gallon Hot Water Tank on Left, 105 Gallon Preheat on Right

There are two types of solar energy, photovoltaic’s which produce electricity and solar thermal which produces heat. Photovoltaic’s gets all the attention as electricity is the universal power medium and cheap photovoltaics could revolutionize the world. While photovoltaic’s are still rapidly developing since its invention over 50 years ago by Bell Laboratories solar thermal has been a developed and proven technology for many years. Solar thermal uses the sun’s energy to heat a liquid. It is the same concept as placing a garden hose in the sun for an hour: the water will become hot. There isn’t much technology can do to improve heating a liquid so most of the solar thermal technology from the 1980’s is the same as today. There has been one new additional technology which is evacuated tube solar panels. Evacuated tubes are slightly more efficient than the older flat plates panels and work better in cloudy and colder climates. The downside is that they are costlier and to some people not as pleasing on the eyes. Since solar thermal is a mature technology the prices are very reasonable and the payback is just a matter of years compared to 10+ for most photovoltaic installations.

Over the next week I will be updating the site with information regarding the solar thermal installation installed at my family’s house.

I finally got some new blades for the wind turbine.  The old blades worked, but they were not yielding the results I was looking for.  The old blades had a large surface area and were heavy.  This gave them a huge amount of torque and allowed them to start in the slightest of breezes.  The issue is that on moderately windy days they won’t spin fast enough to reach the generator’s cut in voltage of 12V.  I purchased a set of 6 blades modeled after those on the AirX wind turbine.  The blades are made from a durable plastic and are designed to spin very fast: over 1000RPM’s!

I built a new temporary stand for the turbine so I could easily test it outside without the need to put up the 10Ft tower.  Today was extremely windy in Rochester with sustained 20-30MPH winds; a perfect day to test the blades.  The blades worked great and allowed the turbine to reach an open circuit voltage of 32V.

Looks Good!

Spinning at over 600 RPMs

http://media.csh.rit.edu/public/New%20Blades.flv

The blades look like they are spinning much slower in the video due to the camera’s frame rate.  No the blades didn’t stop and reverse, it is an illusion do to the camera.

I recently set up my Asterix server with GrandCentral, a VOIP service from Google. Asterix is a great softPBX and I used to link some of my friends and family members so we could make free calls. Many devices today support SIP such as Cisco VOIP phones and the Apple iPhone. While talking with friends was cool, if they didn’t have a SIP supported device I couldn’t call them. The issue with VOIP is that you need PSTN termination if it is to be useful for the outside world. Like any service this costs money, but with GrandCentral I can make and receive calls for free. This has expanded the use of my Asterix server and has allowed me to greatly cut down on my cellular minutes. I mainly use GrandCentral with my Cisco 7960 VOIP phone, but it also works on my cell phone with a SIP client. This allows me to be mobile and still use GrandCentral and my Asterix server in combination with Sprint’s EVDO service for free calling. Sadly GrandCentral is no longer accepting beta testers, but hopefully it exits beta so everyone can enjoy free calling.