Recently debuting at #1 on Digg.com was a story on a laptop battery that could last 30 years. This story got more Diggs than a video of a monkey pwning you in Halo 3 would have, but no one seemed to ask, "Really...for real?"

The technology is actually quite fascinating. It's a "betavoltaic" power source. These actually exist. And they work by getting together a lump of radioactive material (like tritium) that emits beta particles and then converting the beta particles to electricity. It's just like photovoltaics...except instead of photons, it's beta particles.

This device isn't a battery, it's actually a power source, and it will indeed continue producing power for 30 years (the half-life of tritium is 12 years, so it will be producing roughly 25% of its power 30 years from now.) But the article doesn't point out that there are significant problems with the technology, specifically when using it as a laptop battery.

So what are the problems?

1. To power a laptop, you'd need about 50 lbs of tritium. Researchers plan on surmounting this by trickle charging a battery with the betavoltaic. This way, when the laptop is not in use, the battery would be recharged by the betavoltaic power source. But while using the laptop, you'd experience nothing more than an increase in life...not a 30 year battery.
2. While the article states that these laptops would run cooler than Li-ion laptops, that's quite wrong. Betavoltaics lose about 75% of their energy as heat, and as designers will be required to include Li-ion batteries anyway, I imagine, if anything they'd be hotter.
3. At the end of its, life the power source would be completely innert, but during use, it wouldn't be. Moderate shielding can easily block beta waves, but if the battery were damaged, and then you placed it on your "lap" I would hate to think of the consequnces.

I'm not saying that this technology isn't useful. In fact, it's very useful, particularly for space missions requiring low but constant power. Or for any device that needs a low voltage for a long period of time and is difficult to access.

The possibility of trickle charging a Li-ion for increased life is intriguing, and certain low-power cell phones may someday be able to run 100% on betavoltaics. But a 30-year laptop battery, I'm afraid, doesn't look likely.

Via ZDNet

Power storage is a critical challenge for adoption of intermittent renewable power sources and also for being able to help shift base load to peak load requirements. There are many approaches being pursued, but the Energy Island, conceived for off the coast of the Netherlands, is an extremely innovative concept.

The Energy Island

incorporates a new concept in pumped hydro storage — an inverse offshore pump accumulation station (IOPAC).

On the Energy Island when there is a surplus of wind energy, the excess energy is used to pump seawater out of the interior "subsurface-lake" into the surrounding sea. When there is a shortage of wind power, seawater is allowed to flow back into the interior "lake" through commercially available generators to produce energy.

Ahh, pumped hydro storage. Something which we know well and that has been around since the late 19th century. Pumped storage works well as a partner to wind power, storing at roughly an 80-90% efficiency. Pumped hydro storage thus enables reliable power supplies with wind power.

Well, there is something new and innovative here. KEMA, Lievense and the Das brothers have designed an artificial island that would, in essence, be somewhat like a Pacific atoll, but the inner water surrounded by the outer ring would be sealed off from the larger ocean. The interior reservoir would be 50 meters deep, enabled by the mud of the seas off the Netherlands. And the island (the dikes/outer ring) would be made from the materials dredged to create the reservoir.

On that outer ring would be a long line of wind turbines for sending power ashore. When producing excess power, sea water would be pumped out of the enclosed lake into the surrounding sea. When there is greater demand, sea water flows back into the "lake," driving generators. The analysis to date suggests a 12-hour power delivery at 1.5 gigawatts (roughly equal to three coal-fired plants). The KEMA analysis suggests a total annual storage capacity of 20 GWh or "enough energy to offset 500 to 840 kilotons of CO2 emissions."

Note that the Energy Island truly does seem to be an island of energy. Not only the wind mills and electrical generators from sea water, but as well a chemical plant (better far from an urban area) and a liquid natural gas (LNG) terminal.