There are so many benefits that the green revolution can bring to people and to the environment but I have to suggest that solar powered hearing aids are very near the top of the list. There are two massive benefit that these could provide. For one, we all know that hearing aids just plow through batteries which are filling land fills around the world as I write this. Certainly the batteries are small but they add up and they are toxic. So using solar power would slow the ridiculous production of the batteries.
More importantly, people in hot/poverty stricken countries would be more likely to be able to afford to operate hearing aids. It is a simple fact that the cost of batteries makes operating hearing aids impossible for millions of people around the world. Using solar power would eliminate the cost of replacing them.
The challenge I imagine is designing a solar cell that is small enough to still work on a hearing aid whilce capturing enough power. The solution can not be a massive hearing aid, that simply will not fly. I also imagine that the solar technology will lead to a steep initial price. But this will lower as competition enters the market. Raise a toast to solar powered hearing aids. They are a very good thing!