SINGAPORE - After tutor Roy Chan made the switch from national grid operator SP Group to an Open Electricity Market (OEM) retailer in 2018, he saved, by his estimate, more than 30 per cent on his electricity bill. When his fixed-price plan with Senoko Energy expires this month, the 35-year-old will have to renew it at a rate of 24.9 cents per kilowatt hour (kwh) - nearly 60 per cent more than the rate of 15.89 cents per kwh he was previously paying. Consumers like Mr Chan are sitting up and taking notice of rate hikes by OEM retailers driven by soaring electricity prices and fuel costs. This is especially as Singaporeans settle into a new normal of working, learning and recovering from home, with a sustained, significant increase in power consumption expected. Those needing to recontract told The Straits Times that they are mulling over their options as the gap continues to narrow between regulated tariff rates and OEM rates - from as high as 30 per cent three years ago to around 10 per cent today. Observers also warned that more OEM retailers would shut down as their profit margins shrink and market consolidation takes hold. Singapore's fourth-largest electricity retailer iSwitch ...