GST calculations for my 1 mw solar power plant

Sorry i pad him 49L and he return me back 110L

I mean i pad him 49L and he returned me 10L back

As per the nature of solar power projects, GST applicability mainly depends on the contract structure, scope of work, and invoice breakup. In many EPC contracts, the 70:30 mechanism has been considered, but in some cases transmission line and structural work may also fall under works contract services taxable at 18%.

You should properly review the agreement and billing pattern before finalising the GST treatment.

If you still have any confusion regarding the applicability or calculation, you may directly discuss the complete matter with me through the official Beginquest website. After reviewing the agreement and invoices properly, a more accurate opinion can be provided.

For a composite works contract covering a solar power plant installation (including 11 kV transmission line and bay structure), the GST rate depends on how the contract is structured. Solar power generating systems qualify for 12% GST under HSN 8541, and installation/works contract services fall under HSN 9954 at 18%. The 8.9% composite rate (70-30 split at 5% goods) would only apply if the components fall under the 5% renewable energy devices category, which is disputed in practice and carries audit risk for transmission line infrastructure.

Tax Garden put together a [GST on works contracts guide](https://taxgarden.in/blog/gst-on-works-contract-construction-services-india-2026) that covers rate applicability and the documentation needed for composite contracts.