By GCShutter / Getty Images Looking for ways to save energy in the kitchen? One simple way of achieving this is through passive cooking. Here’s how it works. Looking for ways to save energy in the kitchen? One simple way of achieving this is through passive cooking. Here’s how it works. As winter approaches and temperatures start to drop, tips on how to save money when cooking are once again flooding onto the web. One such technique, called passive cooking, is proving particularly popular. This simple method consists of bringing water to the boil in a pan, before adding the food. You let it co…