Property, Plant and Equipment

9 Months Ended

Sep. 30, 2022

Property, Plant and Equipment

Property, Plant and Equipment

7. Property, Plant and Equipment

Property, plant and equipment at September 30, 2022 and December 31, 2021 consisted of the following (in thousands):

	September 30, 2022		December 31, 2021
Land	$	1,165	$	1,165
Construction in progress		473,429		169,415
Leasehold improvements		18,213		2,099
Software, machinery, and equipment		157,018		112,068
Property, plant, and equipment		649,825		284,747
Less: accumulated depreciation		(42,557)		(29,124)
Property, plant, and equipment, net	$	607,268	$	255,623

Construction in progress is primarily comprised of construction of five hydrogen production plants, the Gigafactory in Rochester, NY, and our facility in the Slingerlands, NY.  Completed assets are transferred to their respective asset classes, and depreciation begins when an asset is ready for its intended use. Interest on outstanding debt is capitalized during periods of capital asset construction and amortized over the useful lives of the related assets. During the three and nine months ended September 30, 2022, the Company capitalized $4.0 million and $9.8 million of interest, respectively.

Depreciation expense related to property, plant and equipment was $5.4 million and $1.9 million for the three months ended September 30, 2022 and 2021, respectively. Depreciation expense related to property, plant and equipment was $13.5 million and $5.2 million for the nine months ended September 30, 2022 and 2021, respectively.