WARRANTIES

Provisions of our sales agreements include product warranties customary to these types of agreements, ranging from 18 months to 24 months following installation for Thin Films products and 5 years to 10 years following installation for Solar Energy products. Our provision for the estimated cost of warranties is recorded when revenue is recognized. The warranty provision is based on historical experience by product, configuration and geographic region.

We establish accruals for warranty issues that are probable to result in future costs. Changes in product warranty accruals are as follows (in thousands):



	Three Months Ended September 30,						Nine Months Ended September 30,
	2012			2011			2012			2011
Balances at beginning of period	$	14,057		$	14,296		$	14,719		$	12,949
Increases to accruals related to sales during the period	2,650			2,498			6,350			7,542
Warranty expenditures	(1,832		)	(2,073		)	(6,194		)	(5,770		)
Balances at end of period	$	14,875		$	14,721		$	14,875		$	14,721

We also offer our Solar Energy customers the option to purchase additional warranty coverage up to 20 years after the base warranty period expires. Deferred revenue related to such extended warranty contracts was $19.2 million as of September 30, 2012, of which $0.4 million is classified in Customer deposits and $18.8 million is classified in Other long-term liabilities in the Condensed Consolidated Balance Sheet as of September 30, 2012. As of December 31, 2011, deferred revenue related to extended warranty contracts was $12.9 million, of which $8.0 million is classified in Customer deposits and $4.9 million is classified in Other long-term liabilities.