Where I live in Ohio, we are in a deep freeze with lots of snow. I feel so bad for birds and animals outside!
Recently, I purchased a birdbath water warmer. It is an electric powered model, quite entry-level, but it really does work! Each bitterly cold day, I peek through my window to see if the water has frozen, but it does its job and keeps the center clear of ice.
The next test was to see if my birds would really use it- and I am happy to say that I have happy birds! I have seen several birds dipping their beaks into the melted center. This weather has also done a number on my corn supply! I must start buying a bigger bag- it would be great to grow my own.