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This blog series centers around a seemingly simple question: Can changing my electric rate plan from Georgia Power’s Standard Residential Service plan to one of the utility’s other residential options save me money? While I enjoy the suspense of a good mystery, I won’t keep you waiting—after crunching the data, it’s clear that the answer is no. 

Shortest blog post ever? Not quite. I’ll take you through the options that are available to me as a Georgia Power residential customer and explain how I used my family’s data and electricity usage insights to reach that conclusion. It might help to review the two previous posts to brush up on electric rates and bill charges as well as how electricity is used at home. 

Georgia Power Residential Rate Options 

Georgia Power offers seven residential rate plan options, but I’m only going to evaluate five of them since both the Flat Bill and Pay by Day rate plans use rate structures from other plans, just with different ways to pay. Those two are better characterized as alternate payment plans. The five plans I’m assessing are detailed below, and you can check out the most current information on Georgia Power’s rate plan options on their site 

 

Data Analysis 

I examined my family’s hourly electricity usage for a 12-month period (Feb. 2021 – Jan. 2023) to conclude that Georgia Power’s Standard Residential rate plan results in the lowest total electricity bill for my family. Nights & Weekends worked out to be slightly more expensive. The most expensive option, Smart Usage, would increase my bill by more than 20%.  

 

Estimated Annual Bill by Rate Plan and by Billing Component (Graph & Table)

Nearly everyone who has had or helped with math homework will be familiar with the directive to “show your work.” If you want a deep dive into the numbers, you can find it here

Some Context about My Results 

These results and my rate decisions are personal – they are specific to my family’s electricity use. Don’t assume that what is true for me is true for you and base your decisions on it—but do think about how your own situation parallels or differs from what I describe. For context, here’s how my family uses electricity:  

  • Low Annual Electricity Use: My family uses about 7,300 kWh of electricity per year (610 kWh/month), about 45% below the annual use of the average Georgia Power residential customer. Most of our lights are LED, and we have multiple ENERGY STAR appliances. Our electricity use is also low partly because we have a natural gas furnace and hot water heater. If you have all-electric end-uses or charge an electric vehicle, you might use more electricity and reach different conclusions because of it.   
  • Natural Gas Heat and Hot Water: Because we heat our house and water with natural gas, the pattern of our electricity use also differs from those customers with electric heat pumps and hot water heaters. We probably use relatively less electricity in off-peak periods, have slightly higher peak demands in summer months, and have a lower average load factor (keep reading).  
  • Low Load Factor: Load factor is an industry standard way of measuring how a customer uses electricity (0-100%). My family is a low load-factor customer with monthly load factors from 12-23%. You might describe low load-factor customers as “peaky and inefficient” and high load-factor customers as “steady and efficient.” 
  • AC Peak: My family’s peak electricity demand appears to be mostly driven by air conditioning. If I isolate the 10 single hours in the year with our highest use, they are all in summer months (June to August) from 1:00 – 10:00 pm. If I zoom out to focus on the top 20 single hours, 17 of them occur on summer days between 1:00 – 10:00 pm. We have a reasonably efficient AC unit (16 SEER condenser), but AC still drives our peak. My guess is that’s because our house leaks like a sieve. We live in a one-story 1928 Craftsman bungalow with single-pane, double-hung windows and no insulation in the walls or floor (over an unconditioned basement/crawlspace).  

Observations by Rate Plan 

Standard Residential vs. Nights & Weekends 

For this project, I’m using mostly 2022 data and focusing on the rate plans that were in effect in 2022. It’s worth noting that the structure of the Standard Residential service was modified, starting in 2023, and no longer has a declining block energy rate in winter. The winter energy rate is flat in the new version (R-26). 

It’s also worth emphasizing that this is an annual analysis. In eight months of the year, Nights & Weekends results in a lower monthly for my family, but the Standard Residential rate produces enough savings in the summer to offset this advantage. Looking at a few select months is unlikely to give you the full picture.  

Monthly Bill Comparison

Plug-In EV

Any Georgia Power residential customer in a separately metered dwelling can choose the Plug-In EV rate. You don’t have to charge or own an electric vehicle (we don’t). I wondered if the Plug-In EV rate might prove a dark horse winner. It could be if we had enough overnight electricity use to take advantage of the cheap Super Off-Peak rate (1.5 cents per kWh), but looking at the numbers, that’s not the case for us.  

One reason the plan did not yield us a lower bill is its higher “shoulder” or Off-Peak rate that offsets its cheap Super Off-Peak rate. The Plug-In EV Off-Peak rate (7 cents per kWh) is 35% higher than the Nights & Weekends Off-Peak rate (5.2 cents per kWh). I replicated Georgia Power’s Plug-In EV infographic, adding the same values for the Nights & Weekends rate. Most of my family’s use falls in the Off-Peak bucket in either plan (68% Off-Peak usage annually for Plug-In EV and 90% Off-Peak for Nights & Weekends), so the higher Plug-In EV Off-Peak rate has an impact.  

 

Rates for Time of Use “Buckets” for Plug-In EV and Nights & Weekends

Smart Usage

Because the Smart Usage rate incorporates a demand charge along with a low average energy cost, the rate is sensitive to the “shape” of customers’ electricity use. A customer with steadier, flatter electricity use does better on this type of rate, while a peaky customer does worse. A load duration curve can be helpful to visualize the relationship between your peak and average use and to understand the number of hours in which you have peak electric use. The figure below, reshared from my last post, shows the load duration curve for my house over 365 days (8,760 hours) arranged from highest to lowest use.  

 Our hourly electricity demand was 4 kW or greater in only 55 hours (0.6% of the time), whereas our hourly demand was somewhere between 0.5 kW and 1.5 kW (inclusive) in 3,755 hours (43% of the time). With a significant spread between our peak use and average use, a demand rate like Smart Usage is a worse fit for us. A household with flatter, more consistent use may fare better with that type of rate. 

Hourly Load Duration Curve for My Home for 8,760 Hours (Feb 2022 – Jan 2023)

 

Georgia Power has promoted broader adoption of the Smart Usage rate plan in its last two rate cases, saying on its site that by “making small changes to how and when you use energy, you could save on your annual energy bill.” I estimated the amount I would have to reduce my monthly peak demand (all other factors the same) to yield a total bill lower than my bill under the Standard Residential rate. This is an over-simplification, but it looks like my family would have to cut its peak monthly usage 33% to achieve this result.  

I don’t think it’s realistic that my family cut its peak demand by a third while ensuring we don’t slip up in any single hour.  

Pre-Pay

The Pre-Pay plan is easy to rule out considering that it uses a fixed per-kWh summer price and a fixed per-kWh winter price. We use nearly the same in both Summer and Winter categories, offsetting any winter savings with higher summer rates. 

 

Breakdown of My Annual Energy Use by TOU Bucket

What If We Install Solar? 

One big energy cost-saving measure I mentioned at the outset of this series would be to install rooftop solar. Considering this option raises the question of what happens to our electricity costs if we install a solar system. In the next post, I’ll tackle that question, including how my hourly electricity use data helps me size a solar system, which electricity rate “values” rooftop solar the best, and which electricity rate yields my lowest total bill. Stay tuned!   

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Kevin Kelly

Electric Bills Decoded is Southface Institute’s series exploring how Georgia Power residential customers can use data to help determine whether changing their electricity rate plan can lower their utility bills and offset recent rate hikes. Follow along to understand different types of rates and charges; identify electricity usage patterns; use your data strategically; consider the impact of going solar; and learn about battery storage as a cost-saving tool. We’re decoding it all!

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