Not long ago, I had reached my limit when it came to batteries. We recycle batteries in my home town, but they were piling up faster than I could take them to the recycle center. We were buying AA batteries by the 50-pack and it seemed every time I went to the store we were buying another pack. So finally, I made the investment into rechargeable batteries. I was pleased to find a number of the major battery culprits had specialized rechargeable packs (like the game console controllers). Well, I was proud to say our battery consumption had gone way done, and my trips to the recycle center dropped as well.
But then my electricity bill went up. Not only that, I couldn't find a convenient outlet in the house in which to plug things in any more. Everywhere I looked, we had little transformers plugged into the wall. I blamed the kids, but I was no better. I did some research and discovered that most of those little transformers were consuming a steady 3W of power even if the batteries were charged (idle state) or the device was not even plugged into the transformer (standby state). So, despite my notion to save money, (and go a little green) it would appear I accomplished nothing beyond removing batteries off the shopping list.
A co-worker of mine once described this situation as: 'squeezing the balloon.'
Now I run around the house and unplug transformers, lecturing everybody that they need to monitor their games, computers, phones etc. and disconnect when things are charged. At least my trips to the recycle center were spent in relative peace and quiet.....
Just like in real life, we run into these 'balloon squeezing' situations in engineering all the time. It happens every time we solve a problem in one area, but end up creating a new problem in an area which previously wasn't a problem. Most times we can anticipate the problems, but it is still surprising how often we don't.
I see one such dilemma brewing now in the mobile world. Mobile demand for years has caused operators to jump through hoops trying to provide sufficient coverage and bandwidth to their customers to keep them happy. Initially the strategy was to put cell towers everywhere. But people objected on the grounds that they were unsightly and output potentially dangerous radio energy. The operators responded by taking the cell sites out of "sight," so to speak. [They placed them on business roofs and made them smaller, (microcells, picocells etc.)]. Now in an effort to provide enough data capacity, the operators are looking to replicate their radio bandwidth even more by going with femtocells. It is interesting to note however, that the consumers are going to be asked to place the femtocells in their homes. I'm sure the operators will package them in some sort of aesthetically pleasing way, but the proximity of RF energy in every home is liable to bring new howls of protest in the future. We might even have to place signs on our front doors to alert people as to whether we have an RF-free home or not.
My cell phone is running low on power.... I have to plug it in.