PREPAID EXPENSE AND OTHER CURRENT ASSETS
 12 Months Ended
Dec. 31, 2017
Prepaid Expense and Other Assets, Current [Abstract]  
Prepaid Expense and Other Current Assets Disclosure
5. PREPAID EXPENSE AND OTHER CURRENT ASSETS
 
 
 
At December 31,
 
 
 
2016
 
2017
 
 
 
 
 
 
 
 
 
 Refundable deposits(1)
 
$
1,821,545
 
$
7,927,825
 
 Prepaid rental fees(2)
 
 
-
 
 
1,652,826
 
 EPC Warranty reimbursement receivables
 
 
-
 
 
132,007
 
 Others
 
 
72,045
 
 
830,164
 
 
 
 
 
 
 
 
 
Total prepaid expenses and other current assets
 
$
1,893,590
 
$
10,542,822
 
 
(1)
As of December 31 2017, refundable deposits mainly represented refundable deposits for the bidding of the project asset construction rights.
(2)
As of December 31, 2017, prepaid rental fees mainly represented rooftop rental payments for solar systems for one year.