In double-sided energy markets, both the generation side and the demand side submit bids to the energy market for market clearing. It creates opportunities for load aggregators or energy retailers to earn incentives from by demand response (DR). However, the opportunity to participate in the energy market also poses challenges to energy retailers that appropriate bidding strategies must be applied to avoid penalty in case the
promised load shifting cannot be achieved. In this paper, the DR programme in the wholesale energy market of Singapore is briefly introduced. Under such scenario, we propose bidding strategies for energy retailers to manage demand side resources and participate in the DR programs to maximise the expected profit. Our proposed optimal bidding algorithm is solved using the Gaussian approximation algorithm, which is of very low
complexity as it is independent of the number of loads. The proposed algorithm has low communication requirements because only data concentrators and smart meters are required in the implementation.