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SOLAR POWER SYSTEMS, NET
12 Months Ended
Dec. 31, 2021
SOLAR POWER SYSTEMS, NET  
SOLAR POWER SYSTEMS, NET

7. SOLAR POWER SYSTEMS, NET

Solar power systems, net consist of the following:

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At December 31, 

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At December 31, 

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2020

    

2021

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$

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$

Solar power systems in operation

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182,232

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117,339

Solar power systems under construction

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6,565

​

4,684

Accumulated depreciation

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(30,535)

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(13,760)

Solar power systems, net

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158,262

​

108,263

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Depreciation expense of solar power systems was $6,379, $6,396 and $11,212 for the years ended December 31, 2019, 2020 and 2021, respectively.