It is proposed to install thermal insulation in a residence to save on the summer-monsoon season air-conditioning costs. The estimated yearly saving is $20$ thousand rupees. The cost of installation of the insulation is $150$ thousand rupees. The life of the insulation is $12$ years. For a compound interest rate of $9 \%$ per annum, the minimum salvage value of the insulation for which the proposal is competitive, is $\_\_\_\_\_\_$ thousand rupees (rounded off to nearest integer).
