Behold, an extensively tested method of laundry technologies, honed over centuries!  Anyone will tell you that line-drying your clothes is a serious saver. It certainly is less convenient than transferring into the dryer, and not appropriate for all lifestyles, however.

Pros: Free, there are discrete indoor methods, easier on your garments, saves tons of C02 from the atmosphere, dries faster, larger clothing amounts

Cons: Not all city aesthetic ordinances support outdoor drying, time spent wrangling those pins

The consensus seems to be, depending on the number of loads you clean and kids living at home, line drying will save you around $150 per year.
The outdoor season begins in a month or so.  After hanging up a couple of baskets in late July, the beginning of the line may already be nearly dry.

An even more green/cost-effective solution is not doing your laundry at all, but there also may be sanctions in your household against that measure as well.