Here's to not taking time off. Back in the summer of 1958, Jack Kilby, a new employee at Texas Instruments, hadn't accrued enough vacation time to take off the days at the end of August when TI shut down. Instead, he stayed at the job and sketched out an idea he had been contemplating. It was the integrated circuit. After the vacation, Kilby's boss reviewed the sketches told him to go ahead. On September 12, 1958, he tested a prototype for company executives (see picture below.). It worked. Although Kilby's prototype did not become the essential building block for the chip industry (the integrated circuit Intel co-founder Robert Noyce showed off a short time later turned out to be design everyone adopted), Kilby was first. And in 2000, he got a Nobel Prize for it. (Noyce would have probably shared the award but he had died years earlier.) And what does it have to do with clean energy? Semiconductors and software are the essential building blocks for the energy efficiency business. The cleanest kilowatt is the one that doesn't get used. Utility CEOs like PG&E's Pete Darbee say that efficiency is a higher priority than solar. Trilliant, Gainspan, Tendril, SynapSense and a whole host of companies are exploiting WiFi, ZigBee and other PC-centric technologies for data centers and smart meters. VCs in recent quarters have begun to wake up to energy efficiency and put more money into these companies. Devising chips and software to save energy is also in some ways easier than trying to build solar or geothermal plants. The technology challenges are somewhat understood and many of the companies that will make products for this market already have factories. Thus, there's no massive capital outlay required. TI, in fact, unfurled a new line of microcontrollers this week (see second picture) called Piccolo, which can control the power consumed by air conditioners and other devices. Freescale has also been active in lately in this market, helping a company devise a system for increasing gas mileage on scooters.