Tucson Electric Power (TEP) has recently begun offering new pricing plans.
Out of the four plans that TEP offers, the residential Basic pricing plan is most compatible with solar and is thus the plan we recommend for solar homeowners.
1) Time-of-Use (TOU)
The idea is lower energy charges by shifting a majority of your usage away from on-peak hours when customers typically use energy the most.
Time-of-use and solar: This plan will move away from the 1:1 exchange rate by decreasing the value of energy during the day and increasing it during TEP's peak periods. Meaning, when you are not at home consuming electricity during the day, the value of your solar production will be at the lower rate. When you return home at the end of the day, where the solar production is low or zero, you will purchase electricity at the higher rate. This plan makes sense for customers who do not have solar, and who can avoid using energy during the peak periods.
2) Peak Demand
The idea is to space out your use of large appliances and equipment such as air conditioning, lighting, computers, copiers and printers during on-peak hours to reduce your peak energy demand and increase your savings.
Peak Demand and solar: The majority of our clients would not do well on this plan. Although the energy charges are lower, you pay the highest power usage during peak demands. There are no advantages with this plan if you get most of your energy from solar. However, if you are a high energy user (more than 1500 kWh/month) and get half or less than half of your energy from solar, this plan may work for you if you are very proactive with your usage. Under this plan, you would need to shift your large appliance usage to operate when the solar is producing (i.e. not at the end of the day) and decrease the use of power at other times. The best way to manage your usage under this plan is with a "demand controller", which prioritizes the operation of large appliances such your AC and water heater.
3) Demand Time-of-Use (TOU)
The idea is to shift the majority of your usage to off-peak hours and avoid the simultaneous use of equipment during on-peak hours to maximize your savings.
Demand Time-of-use and solar: This is a more complex version of the Time-of-Use (TOU) plan. This plan will not work well with solar unless you are looking to actively manage your energy and power usage. Solar customers can expect to see higher bills with this plan.
This plan is TEP's traditional "two part" rate. There is a fixed part of the rate for having service, now set at $13/month, and a variable part of the rate based on the amount of energy you use each month (in kWh). Under the current Net Metering rules, energy produced for customers subscribing to this plan either offsets energy usage from TEP, or is back fed into the grid and you are credited for later use on a 1:1 basis. In other words, if you are paying $0.11/kWh for electricity, every kWh your solar electric system generates will be worth $0.11. This plan is the simplest to work with for solar customers, and will provide the most savings in almost all cases.