Coach, you could run a windmill but a compressor would give you more control and ensure that you have aeration when you need it. You don't have to run power to the pond assuming that your pond is within 1000' of your existing power source. You can place the compressor at the existing power and run 1.5" PVC (glued) from the power to the pond edge. Then just pump the air into the PVC and out to your diffuser.
I wouldn't expect too many problems your first year. However, as a general rule of thumb, a bottom laid aeration system will help the existing bacteria consume about an inch of organic sediment per year. An ounce of prevention is worth a pound of cure so get started with aeration ASAP.
