Nuts and Volts - February 2012

MICRO-SCALE ENERGY HARVESTING

CIRCUITS AND DEVICES CONTINUED

At first glance, it looks like the son of a Rube Goldberg joke, but the drain clamp in the photo is a real life application of the Thermobility™ energy harvesting platform from Nextreme Thermal Solutions ( www.nextreme.com). Nextreme has marked its turf as "the leader in micro-scale thermal management and power generation solutions," and it specializes in using thin-film thermoelectric technology to convert thermal energy into electric power for various autonomous self-powered applications. When incorporated as a plumbing subsystem, thermal energy from water supply lines is converted to electricity that can be used as a source of power for LED indicators, hands-free faucets, soap dispenser solenoids, and wireless transmitters for data acquisition applications. Harvested power can help reduce the size of batteries or sometimes eliminate them entirely.

The concept is also useful in the HVAC industry, where wireless power generators can be used to drive temperature, humidity, and airflow sensors. They can harvest energy from both hot and cold temperature differences and can even store energy for on-demand power. Maybe it's not as silly as it looks. ▲

■ Nextreme's Thermobility drain clamp harvests energy from plumbing fixtures.

■ The TLM 1550 military/ aerospace-grade battery.

BATTERY OFFERS 25 YEAR OP LIFE

If you're looking for batteries that offer high power, long life, and extended storage (e.g., for military/aerospace systems, defibrillators and other portable medical devices, communications systems, wireless sensors, and other telemetric and remote devices), you might be interested in some products offered by Tadiran ( www.tadiranbat.com). An example is the new TLM 1550 — a high-voltage/high-rate AA lithium unit. It offers an open circuit voltage of 4.0V and the ability to handle pulses of up to 15A, with 5A maximum continuous load. The TLM is designed to handle extreme environmental conditions, including a self-discharge rate of less than three percent per year at room temperature and a temperature range of - 40°C to +85°C. It is also said to be extremely safe in operation and has undergone extensive safety tests, including nail penetration, crush tests, high temperature chambers, and short circuit and charge tests. On top of that, the company claims a 25 year operating life for its products. You probably won't be putting a set in your digital camera soon, though, as they are not exactly cheap. Allied Electronics ( www.alliedelec.com) lists them for $41.65 each. ▲

PONG TURNS 40

It seems worth noting that the Atari video game called Pong was introduced 40 years ago this year, rapidly becoming the first video game to gain wide popularity and commercial success. It also marked the beginning of the end for electromechanical pinball machines which, although wonderful devices, were expensive, complicated, and difficult to repair. Also notable is the fact that Atari was the first employer of a certain bedraggled, hippie-type, Pong-loving dropout from Reed College. He was taken on as an electronic technician after informing the personnel director that his only choices were to hire him or call the cops to drag him away. That person was Steve Jobs. NV INDUSTRY AND THE PROFESSION