| Do you have ambitions of putting a Photovoltaic array on top of your house
and disconnecting your electric company? Or, of staying attached to the grid and selling
electricity back to them? This worksheet does a simple, "back of the envelope"
calculation of PV system economics (Please do a more careful sizing before you buy
something!), and can help you understand many of the tradeoffs that are involved in using
this increasingly popular renewable energy technology. Enter information about your
electricity consumption, your cost of service, and your local sunshine, and this worksheet
will help you investigate the relative cost of installing a photovoltaic system that meets
your needs. You can click on the "?" button in any table entry for more
explanation and help. |
| Two other things to consider: An increasing cost of electricity (at
percent per year) will increase the present value of your future grid-supplied electric
consumption, while the time value of money (at percent per year) decreases
it, as well as the present value of yearly PV operating expenses. Comparing the cost of
the PV system to the displaced electricity cost, you will probably conclude that
disconnecting the electric company won't save you money right now. On the other hand, it
is feasible and not incredibly expensive, particularly if you live in an energy-efficient
way. Also, note that if the electric grid isn't near, PV generated electricity may be the
cheapest option. |