What is most spectacular about the buybacks announced this week is not just their size, but also that they are occurring in industries whose fundamentals are at a cyclical bottom or just beginning a cyclical upswing.

• Home Depot Inc (NYSE: HD) -- increased share buyback by $22.5 billion, roughly one-third of its market capitalization
• Expedia Inc (NASDAQ: EXPE) -- buying back 42% of its outstanding stock through a Dutch auction
• National Semiconductor Corporation (NYSE: NSM) -- last week increased its buyback to $2.5 billion, or 27% of its market cap.

TheStreet.com has an excellent chart on share buybacks announced during the last few months.

Home Depot is buying back stock while the housing construction market is still bottoming, Expedia just started reported good results earlier this year and National Semi said in its most recent conference call that the wireless semiconductor market is exiting an industry bottom.

Why is there so much cash available for these massive share buybacks? Huge returns on invested capital (ROIC) is the answer. US companies have done a great job earning their cost of capital. Even if companies do not grow revenue quickly, as has been the case with Home Depot, they generate massive free cash flow. The same can be said of Expedia and National Semi.

The massive buybacks being announced just as industry fundamentals are bottoming or beginning an upswing is a very bullish signal for these stocks.

Interested in investing in wind power? Whether it's because you see that the demand is forecast to double within 3 years for wind turbines, or because you're trying to encourage more wind use for personal reasons, how can you go about this?

Kevin Kelleher of The Street points out that it's tough for US investors to find companies that are all about wind power to make the investment. He names some companies you can invest in, but includes GE as one way you could invest in wind power.

1.5% of GE's income last year was through wind power sales. That's $1 billion in sales, hardly a drop in the bucket. Kelleher's other choices are sketchy at best, with US Wind Farming not making any revenue, and Western Wind Energy being in legal trouble.

GE offers the odd benefit of being able to invest in a blue chip company, stable with paying dividends, as well as investing in the future of alternative energy sector that GE is driving and trying to grow. A stock pick for both conscience and safe stock play? That's got to be attractive to some types of investors. Furthermore, GE is clearly a leader in this technology and market, so if you're interested in wind power, a look closer a GE is worth it.

[pic via: kevinzim]