Medical Power Supplies: New Efficiency Standards are Ahead

This week the U.S. Department of Energy (DOE) has published a notice of proposed rule on its "Energy Conservation Program for Consumer Products: Determination Concerning the Potential for Energy Conservation Standards for Non-Class A External Power Supplies." In this document, DOE proposes to determine that energy conservation standards for so-called non-Class A external power supplies (EPS). Class A in DOE terminology refers to single output EPS with nameplate power under 250 watts.

For reference, currently there are three domestic programs that mandate certain minimum efficiency levels of external power supplies: the Federal mandatory standard for Class A EPSs, the EPA’s voluntary ENERGY STAR standard, and California’s mandatory standard for so-called ‘‘State Regulated EPSs.’’ They all apply to low-power single-output units and particularly exclude medical supplies. Did you think the government would let anything to be unregulated? Nah! The DOE is now is trying to regulate efficiency of four more types of external power supplies that do not fall under class A: (1) Multiple output EPS (2) EPS above 250 W, (3) EPS for medical use, and (4) EPS for battery charging. The new proposed rule can affect power supplies for a wide variety of applications such as amateur radio equipment, Xbox 360, nebulizers for home use and other medical equipment, cordless power tools, etc. Note that this rule does not set any specific standards yet; it only positively determines that future standards may be warranted and should be explored in an energy conservation standards rulemaking. DOE will be accepting comments by December 18, 2009, after which it will make an actual determination.

Green Electricity From Cars

This week an Israeli firm Innowattech performed a successful trial of their alternative energy system that generates "green" electricity from vibration caused by passing cars. The system was installed on a 10 meter strip of asphalt on a highway and powered the street lights set up next to this strip. It used special piezoelectric generators embedded in the asphalt 2 inches below its top level. The generators were mounted with electronic cards that fed voltage into a storage system.

Piezoelectric effect in general is the generation of a voltage by certain solid dielectric materials when a mechanical stress is applied to them. It has been known for more then a century, and is widely used in piezoelectric transformers for high-voltage power supplies, various transducers, sensors, cigarette lighters, and other low-power applications. The Innowattech's system called IPEG™ is probably the first practical high-power application of piezoelectricity. According to the company, the installation of their system stretching one kilometer would produce 200 kW per hour on single traffic lane, or 1 megawatt on a four lane highway. Installation of the piezo-generators and electronic cards can be performed during paving of new roads or during the maintenance work. The "traffic energy" can be either supplied back to the drivers by powering the road lights or fed into the electric grid. A variation of IPEG™ can also produce power from pedestrian movement. Harvesting energy from the vibrations created by people walking on the floor is also being researched by East Japan Railway Company, who installed “Power-Generating Floor” in a Tokyo station.

Innowattech estimates the cost of energy harvesting from roads, railways and runways via IPEG™ to be 3 to 10 cents per kilowatt, which is comparable to the cost of renewable energies.

Cheap Small Generators

If you consider buying a cheap small electric generator for emergency purposes, now it's the right time to do it. A year from now you probably won't find a cheap portable generator for sale because of the new EPA exhaust emissions standards that will take effect in 2011. These new standards apply to all so-called Small Nonroad Spark-Ignition (SI) Engines and Equipment with engines up to 19 kW used in household and commercial applications, including lawn and garden equipment, utility vehicles, generators, and a variety of other construction, farm, and industrial equipment. The standards are intended to reduce hydrocarbon emissions from small SI engines by about 35%, and are similar to the requirements adopted previously by the California Air Resources Board (CARB). Of course, as every government regulation, this one comes with a price tag. To comply, the manufacturers have to improve engine combustion and add catalysts. They will have to apply on an annual basis for the certification and pay a certification fee. The extra cost of course will be passed to us, the consumers.

Major domestic manufacturers of gensets such as Generac and Briggs & Stratton, are already CARB-compliant, so likely they will be EPA-certified as well. However their models cost typically twice as much as some cheap imports. Right now you can still buy a small non-CARB compliant portable genset made in China for about $100 per kW power. And if you worry about environment- emergency generators should not be an issue of our concern: maybe you would use them a few hours a year, or maybe you would never use them at all. Of course, portable generators are also used for non-emergency purposes such as on construction sites. However, as CARB's Fact Sheet admitted, small engines (which besides gensets include lawn mowers and a variety of other construction and garden equipment that is used more frequently) comprise only about one percent of California’s air pollution inventory! If EPA wanted to fight this 1% pollution, it could at least allow the non-compliant models to be sold with a label "for emergency use only". Could it be that EPA employees driving to and from their work for years while working on this project, caused a greater environmental impact that all portable emergency generators combined?