3. Balance Sheet Components

Inventory

As of September 30, 2012 and December 31, 2011, our inventory consisted of the following (in thousands):


	September 30, 2012		December 31, 2011
Raw materials	$	83,974	$	12,095
Work in process		25,525		3,665
Finished goods		30,845		26,120
Service parts		18,704		8,202

Total	$	159,048	$	50,082

Property, Plant and Equipment

As of September 30, 2012 and December 31, 2011, our property, plant and equipment, net, consisted of the following (in thousands):


	September 30, 2012			December 31, 2011
Computer equipment and software	$	19,405		$	10,804
Office furniture, machinery and equipment		138,843			21,495
Tooling		126,170			16,584
Building and building improvements		39,628			—
Leasehold improvements		36,084			27,901
Land		26,391			26,391
Construction in progress		145,077			227,461

		531,598			330,636
Less: Accumulated depreciation and amortization		(45,350	)		(32,222	)

Total	$	486,248		$	298,414

Construction in progress is comprised primarily of assets related to the manufacturing of our Model S, including tooling and manufacturing equipment and capitalized interest expense. Depreciation of these assets begin when they are ready for their intended use. Interest expense on outstanding debt is capitalized during the period of significant capital asset construction. Capitalized interest on construction in progress is included in property, plant and equipment, and is amortized over the life of the related assets. During the three and nine months ended September 30, 2012, we capitalized $2.1 million and $5.5 million, respectively. During the three and nine months ended September 30, 2011, we capitalized $1.1 million and $2.8 million of interest expense, respectively.

Depreciation and amortization expense during the three and nine months ended September 30, 2012 was $6.8 million and $13.7 million, respectively. Depreciation and amortization expense during the three and nine months ended September 30, 2011 was $3.7 million and $10.5 million, respectively.

Other Assets

As of September 30, 2012 and December 31, 2011, our other assets consisted of the following (in thousands):


	September 30, 2012		December 31, 2011
Emission credits	$	14,392	$	14,508
Loan facility issuance costs, net		5,922		6,407
Other		1,597		1,456

Total	$	21,911	$	22,371

Emission credits are related to the operation of our Tesla Factory and therefore we amortize the emission credits over the same useful life.

Accrued Liabilities

As of September 30, 2012 and December 31, 2011, our accrued liabilities consisted of the following (in thousands):


	September 30, 2012		December 31, 2011
Accrued purchases	$	12,460	$	19,534
Payroll and related costs		10,106		8,905
Taxes payable		1,762		967
Accrued warranty		1,560		2,044
Adverse purchase commitments		452		111
Other		2,170		548

Total	$	28,510	$	32,109

Other Long-Term Liabilities

As of September 30, 2012 and December 31, 2011, our other long-term liabilities consisted of the following (in thousands):


	September 30, 2012		December 31, 2011
Deferred rent liability	$	5,529	$	3,839
Environmental liabilities		5,300		5,300
Accrued warranty, long-term		4,660		4,271
Other		3,061		1,505

Total	$	18,550	$	14,915