CHENNAI: Coimbatore Consumer Cause has urged the State government to compensate domestic rooftop solar consumers for surplus electricity exported to the grid and withdraw network or wheeling charges, alleging that the existing tariff structure discourages households from installing higher-capacity solar systems.

In a representation to Chief Minister C Joseph Vijay and Prime Minister Narendra Modi, Kathirmathiyon K, secretary of Coimbatore Consumer Cause, said surplus electricity credits remaining unadjusted at the end of the annual settlement period on March 31 lapsed without any compensation to consumers.

It argued that distribution licensees were receiving electricity generated and exported at the consumer's expense without payment, depriving households of the value of the surplus power.

The organisation said the existing tariff structure effectively penalised consumers for generating more solar power and defeated the government's objective of promoting renewable energy. It also argued that distribution licensees benefited from surplus electricity injected into the grid by using it to meet other consumers' demand.

Citing the Kerala State Electricity Regulatory Commission's provisions, under which consumers are paid for surplus electricity at the approved Average Power Purchase Cost (APPC), the organisation urged Tamil Nadu to adopt a similar mechanism.

The organisation also sought to withdraw network or wheeling charges imposed on domestic rooftop solar consumers under the Tamil Nadu Electricity Regulatory Commission's tariff framework with effect from October 22, 2021. It said consumers had to pay these charges even when their solar generation exceeded household consumption and they exported surplus power to the grid.

As an alternative, it suggested that network charges should not be levied when a consumer's solar generation does not exceed the total electricity consumption during the relevant billing or settlement period.

To illustrate the impact, the organisation cited a domestic consumer whose average electricity consumption was around 500 to 550 units. A 5 kW rooftop solar system generated around 1,500 units per billing cycle, leaving a surplus of 950 units, but the consumer had to pay Rs 484 as network charges every two months. This amounted to Rs 5,808 annually, without receiving any compensation for the surplus electricity.

The consumer subsequently reduced the installed capacity from 5 kW to 2 kW to avoid higher network charges, as the smaller system was sufficient to meet household consumption.

In his representation dated November 5, Kathirmathiyon said the present arrangements contradicted the government's promotion of rooftop solar through subsidies and its stated objective of enabling households to benefit from surplus generation.

The organisation urged the government and regulatory commissions to pay domestic consumers for surplus electricity remaining unadjusted on March 31, as per the APPC approved by the commission, and to withdraw network charges levied on domestic rooftop solar prosumers.

The measures would encourage more households to install rooftop solar systems and help them achieve genuinely zero electricity bills.