Hizook

Bonus points for anyone who knows what this device is... I'll give you a hint, it's not a UFO (though it bares a striking resemblance).

OK, I just can't hold off the suspense any longer.  It is called a "pyranometer."  From the Wikipedia page:

Pyranometer clearly showing the instrument main components: glass dome, metal body, black sensor, radiation screen, level and cable. Dimensions: diameter of the dome is 40 mm. Photo shows model SR11 Courtesy Hukseflux Thermal Sensors.

These devices measure the incident solar irradiation by measuring the temperature change of an absorptive material (isolated by the glass domes).  They're used to tell you how much sun-light is hitting per square meter at any time throughout the day.  Luckily, a large dataset has already been compiled (worldwide) for many different locations in the TMY2 dataset.  All of this can be used to predict how much a PV system will generate in a typical year at a particular location, accounting for cloud cover, fog, etc.  For Atlanta (my residence), that works out to about 4.5 kWh/m²/day if you take the daily average. 

Of course, it might just be easier still to just use a NREL chart.

Anyway, I had never heard of a "pyranometer" before...  Good to know.

In the post about electroactive polymers (EAPs), I promised to discuss applications. Here is the first (and one of the more unusual) in a long series. What you see below is an artist's rendition of an EAP-powered ornithopter, or flapping-wing aircraft.

These are being designed by the NASA Institute for Advanced Concepts (NIAC), and were featured in an IEEE Spectrum article entitled "Fly Like a Bird: Flapping Wings Could Revolutionize Aircraft Design" (local PDF copy here). The EAP-powered ornithopter could be used on Earth to autonomously gather scientific data, relay communications, and survey terrain. Of course, such a flying vehicle would be ideal for autonomous planetary exploration (for example, on Venus or Mars), where oxygen deficient atmospheres render combustion-propulsion ineffective. This concept is explored in Colozza's slides on Solid State Aircraft (local copy here). Further, the ability to morph its wing shape allows for improved maneuverability and aerodynamics, which may play an important role in military and commercial manned aircraft.

For construction, they are proposing a "sandwich" of thin-film materials. The three main components are thin-film solar cells (photovoltaics), thin-film lithium-based batteries, and a thin-film Ionic Polymer-Metal Composite (IPMC, a type of EAP) layer along with actuation electrodes.

While this seems technically feasible, there are certainly technical hurdles. One of the more apparent ones that comes to mind is the control of the EAP actuation. The wings built to date have been small and have low actuation frequencies. The planes may be forced to "glide" (like large ocean-faring birds) to conserve energy, and would require much larger wingspans. I'm guessing this is a rather non-trivial technical hurdle. You can see a picture of a small prototype below.

In a later post, I'll show some videos of similar wings in action. In the meantime, there is a video of the proposed ornithopter; however, it has a rather obnoxious introduction by EcoGeek. I'm including it below, but you've been warned (I'm not saving a local copy for that reason).

There was recently an announcement that British households could request and receive a real-time energy meter for their dwellings (such as the ones shown below).

Real-time monitors show people how and where electricity is being used in their homes at that moment in time. More sophisticated models also show what devices are consuming energy.

I think this is a marvelous idea, especially if your home sports a photovoltaic system. It would be great if something similar could be adopted in the US.

Oh yes, I recall seeing a DIY home-power monitoring system, found here. Apparently, the fellow built the software for datacenter power management, so it is feature rich (allows you to add floor plans, saves the data for years, and is accessible over the web). You can see the control panel below. Also shown below are a couple of the low-tech current sensors that are used to measure the power running through each household power circuit.