Japan began imploring people to wrap up for its \"warmbiz\" winter energy-saving campaign on Thursday, despite Tokyo basking in warm sunshine. Citizens of energy-hungry Japan, where all but two nuclear reactors are idle after last year\'s Fukushima disaster, are being given tips on how to stay warm without cranking up the heater -- such as eating hot food. As part of the \"warmbiz\" campaign, which comes after a summer \"coolbiz\" blitz, the environment ministry is extolling the virtues of hot water bottles and recommending shutting the curtains to help keep warm air in. Other advice includes wearing more clothes. The campaign began in beautiful autumn sunshine in Tokyo on Thursday, with the Japan Meteorological Agency forecasting daytime highs of 22 degrees Celsius (72 degrees Fahrenheit) for the capital. Until the tsunami-sparked disaster at Fukushima last March, resource-poor Japan relied on nuclear energy for around a third of its electricity. But public nervousness means authorities are unwilling to give shut-down reactors the green light to restart, leaving Japan more heavily dependent on imported fossil fuels and energy-saving measures.