CHIBA, Japan -- Electronics manufacturers have fought over who has the biggest TV or best speakers for years, but with rising energy prices, efficiency is coming to the fore. Here's a roundup of some of the major announcements at Ceatec, the Japanese version of CES taking place this week outside of Tokyo.

The 32 Watt TV: Although light emitting diodes (LEDs) consume less energy than fluorescent bulbs, the engineering that's gone into fluorescents over the past several years give fluorescents an advantage in certain situations.

Hitachi, for instance, is showing off a prototype 32-inch LCD TV that only consumes about 32 watts, or half the standard light bulb. (A regular advanced TV of this size consumes 100 watts plus.) The TV contains two hot cathode fluorescent lights. Commercial TVs mostly contain cold cathodes. A few manufacturers have put out hot cathode bulb TVs, but have to use ten or so bulbs. With a new bulb developed in its lab and some clever engineering, Hitachi's prototype only needs two bulbs. Hence the low power requirements.

Hitachi had some other gems too. Researchers in the lab have developed a sleep function for TVs. A camera on top of the set focuses on your face. When you get up or fall asleep, the TV is given to understand that you are no longer paying attention and  dims after three seconds. That drops the active power from 150 to 470 watts (depending on the TV)  to 10 watts. When you come back, it flips back on.

It also showed an LED-based LCD TV with LEDs that dim automatically, depending on what is showing on the screen. If the TV shows a night scene, the LEDs behind the dark part of the sky go nearly off. With California proposing energy efficiency standards for TVs, expect things like this to show up in your living room.

Recycling E-Waste with Water: Nearly every major industrialized nation has passed electronic recycling standards, but the challenge is how to make it cheap. Mitsubishi has added a few stages to the process to cut costs.

After a TV or refrigerator is crushed, the iron is filtered out with a magnetic separator. Then the aluminum is extracted from the pile of rubble left after the chipping process (it all looks like a big bowl of Fruity Pebbles) with shifting magnetic fields. A shaking sifter then separates the copper from the plastic.

That's all in use today. The process, though, leaves three kinds of plastic left lumped together. Polypropylene floats, so Mitsubishi has come up with a way to separate it from the rest of the mass with an Archimedean water screw. The two remaining types of plastic are separated with electrostatic chargers. Rather than ship all of this plastic to China, it can be reused. The full process goes live in April.

The All-Knowing Washing Machine: Attendees, or at least the ones from the U.S., liked this one a lot. The Eco-Navi washing machine contains from Panasonic can detect how dirty your clothes are and whether they have big sweat stains. The dirt is detected by a light-activated sensor and the sweat stains are recognized by another sensor that sends tiny electrical impulses through the wash as it spins. In the end, the sensors – which actively monitor how clean your clothes are getting – lead to less energy and water consumption. Electricity consumption drops from 79 watt hours to 72 watt hours and water consumption trickles down to 67 liters from 72 liters per load. It went on sale recently in Japan. It's $3,000 now, but will drop (see picture).

The $40 LED Bulb. This one could be bad news for start-ups like Lemnis Lighting marketing inexpensive LED bulbs. Both Sharp and Panasonic showed off 60-watt equivalent bulbs that consume about 7 watts and only cost around $40. A year ago, such devices cost about $90. The bulbs dim too.

Fuel Cells for the Home: Earlier this year, Panasonic started selling its co-generation system for homes. It takes methane, cracks it, and runs the freed hydrogen atoms through a fuel cell to produce power. It also delivers heat to homes. The 1-kilowatt unit can save about 3,800 kilowatt hours a year and reduce carbon dioxide by 540 to 1,300 kilograms a year, depending on where you get your power from.

The DC Home: It's a long way off still, but companies are already contemplating how to deliver appliances that run on direct current. If you have solar panels on your house (which produce DC), this can save up to ten percent of the energy that gets lost in the DC-AC conversion. Another idea: AC/DC wiring to ease the transition.

Efficient Farming: Fujitsu is placing sensors in agricultural fields to determine soil moisture and other factors. It then mines the data to determine trends to boost yields. Hitachi has developed an application that exploits satellite data to optimize harvest times. This is complimentary.

Thin Film Goes Big: Sharp, one of the largest solar manufacturers in the world, will open a new solar plant in Sakai next year that will make LCD TVs as well as thin film solar panels. Sharp already makes some amorphous solar panels, but the Sakai facility will be the first that produces only thin-film panels. The company declined to comment on what kinds of thin film-cadmium telluride, amorphous solar, CIGS-at Sakai.

Tags: energy efficiency, farming, hitachi, led bulbs, mitsubishi, panasonic, sharp, sony, tv