renewable energy (Score 1)

I would advise against trying to do a grid-tie-in as a hobbiest. It would introduce legal liabilities that you really don't want. That said, there is nothing to prevent you from using alternative energy to power devices locally and reduce your dependence on the utility provider. It is unlikely that it will be cheaper initially so I doubt that you will get net savings in the short-term but any device you take off of the grid will stop contributing to your utility bill. You can do this by using alternative energy sources to charge batteries and then using an inverter to power an isolated set of outlets into which you can plug whatever you have the capacity to power (based on your average charge and discharge rates). This would provide uninteruptable power as well and would be well-suited to your computer and related peripherals. How much you "save" (ignoring installation costs) depends on how much power the devices you place on your alternative "grid" consume. Note that local storage is a practical requirement for most alternative energy systems since they typically have variable output during the course of a day. Grid-tie systems avoid this by supplying utility power to make up for shortfalls and typically will not be eligible for utility subsidies if storage is present at the time of installation. You can also use a "tranfer box" which is a switch which allows connecting your "sub-grid" to either your back-up or utility power but never both. This allows the sub grid to use utility power if consumption exceeds capacity temporarily.