Hi, im on an economy 7 meter and trying to make the best of it. I do not want to put a plug in timer on my washing machine during the night due to the hazards. So im getting up 1 hour before my 7 hour cheaper electricity ends to put a wash on so i wanted to know for my manual washing machine is it more energy efficient to run it on a eco 20' or rapid 15 wash? As i think only these two settings will save abit of money? Thanks