Households will pay more for electricity from today, with electricity tariffs going up by an average of 6.1 per cent for the second quarter of the year.

From April to June, electricity will cost 21.39 cents per kilowatt hour, up from 20.20 cents in the previous quarter.

"The increase is largely due to the cost of natural gas for electricity generation, which increased by 12 per cent compared to the previous quarter," said Singapore Power Group in a statement yesterday.

Since April last year, the quarterly household electricity tariff has seen an increase except between October and December.

The electricity tariff is largely determined by energy costs, which are costs incurred by power generation and fuel. Energy costs made up 73.2 per cent of the new tariff.

The other components of the tariff are network costs, a market support services fee and a market administration and power system operation fee, which are all reviewed annually.

With the latest tariff increase, the average monthly electricity bill for families living in four-room HDB flats will go up by $4.21. This is based on the average electricity usage of such households, which stands at slightly more than 353kwh.

On average, electricity tariffs will rise by $5.04 per month across the board, according to SP.

Families living in one-room flats can expect to pay $1.58 more per month on average, while those living in bungalows may have to shell out $28.48 more.

SP reviews the electricity tariffs quarterly based on guidelines set by the Energy Market Authority, the electricity industry regulator.

This includes pegging the cost of fuel to the average natural gas price in the previous three months.