This question needs to be answered by those using storage heater how much they pay extra for electric bill after installation. Also, if you connect it to washing machine it save you even more.

If u r planning to have storage heaters for 4 bathrooms (RM 500 each = RM 2k) while getting a solar is only RM 3k+. U get hot water instantly, save on electricity bill and price difference very little. Averagely, 1 storage heater is 35 litres, 4 = 140 litres while a SOLAR POWER L60 has 270 litres of hot water. How much u save is how much u use and when u use it. Ofcoz, if u use when there is sun light, the solar heater could provide more than 270Litres of hot water per day.