My Parents and Grandmother live near Tokyo, and they had to live with limited electricity last month. Tokyo and the surrounding areas have had a mandatory black out, which they take turns shutting off their electricity for 2-4 hours a day. It seems there is no plan going on right now, but since it's getting warmer and spring and summer time, I believe that a lot of people are continuously trying to save their energy usage, here and there in their life's.
When I cook and use water, stove or oven, and electricity, I can't stop think of my family and friends in Japan. Fortunately I can use these basic necessities as much as I want and anytime, but now I am really aware of using energy smarter than before. Trying not to keep running water, turn the light off, etc...
And when I make miso soup, which uses Dashi stock, I put kelp and dried Shiitake mushroom in a pitcher with water and keep inside a fridge over night. Here, instant soup stock is made without heat next day when you make.
Miso soup is too popular as Japanese soup, but we have other different kind of soups, too. For example, Sumashi-Jiru is a Japanese clear soup, with a taste of soy sauce and salt, instead of miso paste, and sometimes sake can also be added.
The other day, I made my favorite type of soup - Sumashi-Jiru with bean sprouts and egg. This is the soup my mother used to make a lot when I was growing up until I graduate from high school. I believe that she still makes this soup a lot for my Father and Grandmother :)
You can put Dashi stock in a pan, and flavor with soy sauce and salt, then add bean sprouts, and add an egg at the end. It can be finished in 10 minutes. If you have Dashi already, it will be in 5 minutes.