Sarwar will call for the SNP to fill the gap as the cost of gas and electricity is due to rise steeply within days.The energy price cap will increase by £139 to £1277 on October 1 this year leaving 150,0000 Scottish pensioners living in poverty facing a desperate choice.The push from Labour comes after it was revealed that a woman in her 90s starved to death, the first fatality from lack of food recorded in Scotland for at least 20 years.Sarwar will tell conference that the Scottish Parliament