Here’s a solar water heater setup that augments your home’s water heater instead of replacing it. The system monitors a solar collector panel on the roof for temperature. If the temperature is warm enough, a photo voltaic cell powered pump circulates cold water through the system. The heated water returns to the top of the home’s water heater. Unlike the warm-climate solar heater we saw earlier, this one can withstand freezing because it uses silicone tubing in the collector.
[Thanks Marius]
What you see above is a generator that converts heat to electricity. [Reukpower’s] thermoelectric lamp is one of those hacks that makes you scratch your head even though you understand why it should work. The heart of the system uses a Peltier cool, just like the thermoelectric solar generator. When there is a temperature differential from one side of the Peltier to the other a small current is generated.
In this case a candle heats one side and a heat sink cools the other. The tiny voltage picked up from the Peltier’s contacts is then boosted using a joule thief. We’ve seen LEDs powered with a joule thief before, benefiting from their own low power consumption. In this case, the boost circuit is scavenged from an emergency phone charger and probably achieves higher efficiency than if he had built it himself.
[MetroMPG], an environmentally friendly car enthusiast from Ontario, added a tail to his car to increase gas mileage. This 1998 Pontiac Firefly is a sibling of the cheap and popular Geo Metro. He had already done some work to cover a portion of the rear wheel wells to reduce drag. Using cardboard, duct tape, and an aluminum frame he extended the rear of the car by around six feet.
The results are pretty impressive. His extensive testing can be seen in the video after the break and reveals a Miles Per Gallon increase of 15.1% at 90 km/h to get to 64 MPG. The tail is removable but we’re thinking it’s a pain to keep relocating the tail lights from the original body to the removable one.
Now we’re wondering if someone is doing this to our Smurf-blue Metro that we sold to the junk man for $100 back in 2001. It ran great, if you weren’t caught in the cloud of blue smoke coming out the back.
Continue reading “Aerodynamic Tail Makes Geo Metro Even Cooler”
[Willem] has been using an Arduino to monitor temperatures and electricity usage. For the temperature monitoring he picked up some 1-wire temperature sensors similar to those we’ve featured in the past. To pick up on electricity usage he’s not using an amp sensors, but because he’s in the UK he does have a flashing LED on his power meter. There’s a known trick to pick up these flashes with a photo cell to calculate energy usage based on meter readings. Finally, the data from the three sensors (indoor temp, outdoor temp, and energy usage) is piped over the Internet via an Ethernet shield so that it can be collected and graphed.
[Willem] has had the system running for a year. If you’re nosy you can look at the temperature graph generated from his collected data.
[Hydronic] did some tests to make his own current sensor using a c-clamp wrapped with wire. He tried several different cores including an aluminum carabiner, the C-clamp, and what he calls a u-lock (removable chain link). There is some success here that could be improved with cleaner winding and by adjusting readings based on the length of wire used in the wrapping.
This did make us perk up a bit right off the bat. Reader [Mure], who tipped us off about this, suggested that this could be used to make your own Kill-a-Watt without including it in the circuit. We made the jump to house monitoring. We’d love to have a data tracker for our home circuits to curb wasteful energy use. Perhaps we’ll try to make our own sensors and produce a diy Cent-a-Meter.
[Jake] built himself a solar water heater. The system has an 82 gallon insulated water tank and uses a solar collection grid made of PVC pipe. As the water heats, it rises to the top of the collector and runs into the tank while pulling colder water from the bottom of the tank back into the collector.
A sunny day yields temperatures around 130 degrees Fahrenheit. On a cloudy day the water can still be heated to about 90 Fahrenheit. This is about 19 degrees cooler that one might desire but the difference is made up by an electric shower head that heats as the water comes out. [Jake’s] system, seen in the video after the break, allows him to forgo the use of electricity on sunny days, and reduce its use by around half on cloudy days. Continue reading “Solar Water Heater”
How do you convince a power company to let you play with their multi-million-dollar wind turbine? Call yourself an artist instead of a hacker! [Michael Pendry] convinced Siemens to let him install this ‘art’ piece on the rotors of a wind turbine outside of Munich, Germany. It features 9000 LEDs, 3000 on each of the 30 meter blades, and can pump out 20,000 candelas when fully illuminated.
The problem? The blades of the power generator turn extremely slowly compared to fan-based persistence of vision displays. This makes it more of a “long-exposure” display system that is illustrated in some of their press photos. Ok, so the POV is a bit of a let-down, but the display effects achieved are still pretty impressive.
[Thanks Sam]
