Simplest Electricity Monitoring Solution Yet

Monitoring your home’s energy use is the best way to get a handle on your utility bills. After all, you can’t manage what you can’t measure! The only problem is that most home energy monitoring systems are cumbersome, complicated, or expensive. At least, until now. [Kevin] has created a new electricity meter based on Particle Photons which should alleviate all of these problems.

The Particle Photon (we get confused on the naming scheme but believe this the new version of what used to be called the Spark Core) is a WiFi-enabled development board. [Kevin] is using two, one to drive the display and one to monitor the electricity usage. This part is simple enough, each watt-hour is accompanied by a pulse of an LED on the meter which is picked up by a TLS257 light-to-voltage sensor. The display is a Nextion TFT HMI (touch screen) which is pretty well suited for this application. The data is corralled by emoncms, part of the OpenEnergyMonitor platform, which ties everything together.

For a project that has been done more than a few times, this one does a great job of keeping the price down while maintaining a great aesthetic. Make sure to check out the video below to see it in action.

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Two-Axis Solar Tracker

Solar panels are an amazing piece of engineering, but without exactly the right conditions they can be pretty fickle. One of the most important conditions is that the panel be pointed at the sun, and precise aiming of the panel can be done with a solar tracker. Solar trackers can improve the energy harvesting ability of a solar panel by a substantial margin, and now [Jay] has a two-axis tracker that is also portable.

The core of the project is a Raspberry Pi, chosen after [Jay] found that an Arduino didn’t have enough memory for all of the functionality that he wanted. The Pi and the motor control electronics were stuffed into a Pelican case for weatherproofing. The actual solar tracking is done entirely in software, only requiring a latitude and longitude in order to know where the sun is. This is much easier (and cheaper) than relying on GPS or an optical system for information about the location of the sun.

Be sure to check out the video below of the solar tracker in action. Even without the panel (or the sun, for that matter) the tracker is able to precisely locate the panel for maximum energy efficiency. And, if you’d like to get even MORE power from your solar panel, you should check out a maximum power point tracking system as well.

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Reading Power Use Data with a Webcam and Python

As any hacker will attest to, whenever an important tool is missing, you might as well just build a new one! That’s the position that [Matt] found himself in when he was attempting to measure the power consumption at his parents’ house. He left the transmitter for the power meter at home, and so the logical thing to do was to set up a webcam and a python script to monitor his dad’s power meter instead of going back to get his.

The power meter that he had handy was a GEO Minim Electricity Monitor. He found it very difficult to extract the data directly from this particular meter, so instead of digging into any of the communications protocols int he meter, he set up a webcam in a box with an LED and monitored it with a specially-written Python script. The script is able to see the particulars of the meter, and then reports back to the computer with all of the relevant data. [Matt] has put this code up on his project site for anyone to use.

This is a great workaround that doesn’t involve delving too deep into the inner workings of the meter in question. You could always build your own power monitoring system though, if that’s more of your style!

Homemade Gravity Light Doesn’t Last Long but Proves the Concept!

gravity light

After being inspired by the Deciwatt Gravity light, [Steve Dufresne] decided he wanted to try making his own as a proof of concept.

The Gravity Light by Deciwatt is an innovative device designed for third world countries to help eliminate expensive lighting like kerosene lamps. It has a small weight on a pulley which can be lifted up in under 3 seconds. During its slow descent down the weight provides light for 25 minutes! It’s affordable, sustainable, and reliable. It’s also mechanically impressive, which is exactly why [Steve] decided to try making his own.

He’s using a single LED, a small DC motor, a few pieces of wood, an old bicycle wheel, some bicycle chain, and a few jugs of water. The water is connected to the chain which is looped over the smallest gear on the bike. The generator is then powered by a belt wrapping around the outside of the rim. This gives the motor enough speed to generate electricity for the LED. His current design only lasts for about 3 minutes, but he’s already working on the second iteration. Testing systems like this really give you an appreciation for the effort that must have gone into the real Gravity Light.

Stick around after the break to see it in action.

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Boil Off Some White Gas in the Back Yard


[S Heath] is a Coleman lantern collector. Coleman lanterns can run from a variety of fuels, however they seem to run best with white gas, or Coleman fuel. Store bought Coleman fuel can cost upwards of $10USD/gallon. To keep the prices down, [S Heath] has created a still in his back yard to purify pump gas. We just want to take a second to say that this is not only one of those hacks that we wouldn’t want you to try at home, it’s also one that we wouldn’t try at home ourselves. Heating gasoline up past 120 degrees Celsius in a (mostly) closed container sounds like a recipe for disaster. [S Heath] has pulled it off though.

The still is a relatively standard setup. An electric hot plate is used to heat a metal tank. A column filled with broken glass (increased surface area for reflux) rises out of the tank. The vaporized liquid that does make it to the top of the column travels through a condenser – a pipe cooled with a water jacket. The purified gas then drips out for collection. The heart the system is a PID controller. A K-type thermocouple enters the still at the top of the reflux column. This thermocouple gives feedback to a PID controller at the Still’s control panel. The controller keeps the system at a set temperature, ensuring consistent operation. From 4000 mL of ethanol free pump gas, [S Heath] was able to generate 3100 mL of purified gas, and 500 mL of useless “dregs”. The missing 400 mL is mostly butane dissolved in the pump gas, which is expelled as fumes during the distillation process.

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How can the net amount of entropy of the universe be massively increased?


The greatest – and last – question that will ever be asked is, “How can the net amount of entropy of the universe be massively decreased”. It follows then, that the worst – and possibly first – question ever asked is, “How can the net amount of entropy of the universe be massively increased?” While for the former question there’s insufficient data for a meaningful answer, we’ve found the answer to the latter question. It’s a machine designed to waste energy, and the exact opposite of a perpetual motion machine.

The machine is set up along two stories of a building, with cables, pulleys, and levers constantly pressing an elevator button. The device is powered by the elevator doors opening, so when the elevator opens of the first floor, the part of the machine on the second story calls the elevator. This repeats ad infinitum.

Wait. It gets better. Inside the elevator car, there’s a modified printing calculator also powered by the elevator doors. Every time the doors open, it calculates the amount of energy consumed for each cycle of the elevator. It’s a hydraulic elevator without a countersink, so moving down is effectively free, but each cycle of the elevator still uses up 11.8 Kilojoules of the universe’s energy. To make the build a complete waste of resources, the printing calculator neatly empties it’s printed tape into a wastepaper bin.

We’re tempted to call this a [Rube Goldberg] machine, but that doesn’t seem to fit this machine that does absolutely nothing. Calling it a useless box is more fitting, but this is far, far more impressive than a box that turns itself off. Whatever it is, you can see a video of it in action below.

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Scavenging ambient electromagnetic energy


At this very moment, unseen radio waves are bouncing off almost everything that surrounds you. Emitted by everything from radio and TV stations to cell phone networks and satellites, these waves are full of unharnessed energy. That is, until now. Researchers at the Georgia Tech School of Electrical and Computer Engineering have been working diligently to harness this unused energy, and recently unveiled their new antenna technology at the IEEE Antennas and Propagation Symposium.

The team, led by professor [Manos Tentzeris] has been working to develop ultra-wideband antennas to tap into the energy all around us. Using printers filled with a specially-formulated ink compound, they have been able to print these antennas on paper and polymer substrates. The antennas can harness energy stored in radio frequencies ranging from 100 MHz all the way up to 60 GHz, depending on the printing medium.

The team can currently power temperature sensors using television signals, and is preparing a demo in which they will power a microcontroller simply by holding it up in the air. The technology is still in its infancy, but the list of applications is almost endless. We doubt you’ll be powering your TV with this technology any time soon, but it definitely holds promise for things such as wireless sensor mesh networks and the like.

[Thanks, morganism]