Most Mainers likely have heard the recent reports about higher-than-average electricity bills. We are working hand in hand with the Maine Public Utilities Commission and are moving forward to complete a comprehensive audit of the system. To date we’ve learned a great deal.

At the end of October, we replaced an outdated billing system with state-of-the-art software. While we have found some errors that occurred in the changeover to our new system, we can report that the core functions of the system are working properly.

Replacing a nearly 30-year-old structure with the latest technology did result in some transition issues as you might expect that a major system conversion would. To date, we have found 31 separate issues which we have reported to the Maine Public Utilities Commission. What types of issues have we found? Some customers didn’t receive their bills as expected because of delays in mailing. Some customers could not see past usage information. Other examples involved errors in processing security deposit interest rates and refunds. We have made corrections where necessary. Although each of these examples affected small groups of customers, the collective errors, plus the generally high seasonal bills, contributed to confusion and mistrust among our customers.

We are not happy with negative impacts to customers, and have worked diligently to correct each issue and adjust customer bills when appropriate.

As we reported to the Public Utilities Commission, 97,000 of our customers saw monthly bills that were at least 50 percent higher compared with a year earlier. What we have also discovered is that the vast majority of our customers saw more moderate increases or in some cases lower bills.

Why are some customers using so much more electricity but others not?

Each customer is different, so answers can only be found through examining hourly electricity use at each individual property. We have worked with hundreds of customers to identify some of the factors that explain their bills. Space heaters and heat tape, often used to prevent pipes from freezing, can be enormous users of electricity. Daily use of a space heater, even for short periods, can cause electric bills to rise significantly. Users of gas or oil heat consume more electricity in cold weather as well when fans kick on to distribute that heat.

In recent years, thousands of Mainers have purchased heat pump systems, many with the help of rebates. While electric heat pumps can help customers save on oil or propane bills, they are much less efficient in colder temperatures. During this year’s extremely harsh winter, when cold weather set records in December and January, increased electric heat pump use resulted in much higher electricity consumption.

Increased electricity use isn’t the only reason customer bills rose this past winter. On Jan. 1, two major electricity suppliers, NextEra Energy Power Marketing, LLC and Constellation Energy Commodities Group Maine, LLC raised the price of the Standard Offer supply by 18 percent; other competitive suppliers boosted rates by as much as 50 percent.

This expense is separate from CMP’s delivery service, although customers receive both bills in a single mailing from CMP as a convenience. CMP forwards customers’ supply payments to the appropriate suppliers on the customers’ behalf.

Taken together, higher electricity use and increased supply prices caught many by surprise. We understand the impact that high bills have on our customers and we offer free, easy-to-use tools to help customers manage their usage. They include Energy Manager, an online tool that displays hourly electricity use, and Usage Alerts that let customers know when they reach consumption thresholds (just like the notices from cellphone services about data usage). We also offer an online Energy Calculator that customers can use to calculate the cost of running appliances.

Central Maine Power takes seriously our customers’ concerns about bills that are higher than expected and the inconvenience associated with errors that require correction on our end.

We will continue to work with the PUC and its auditors and respond to every customer. Should any issues be found that led to an overbilling or overpayment by a customer, we will fix them and make sure customers are repaid. That is our pledge to every customer we serve.