Robert J. Durian
Executive Vice President and Chief Financial Officer at Alliant Energy
Thanks, John. Good morning, everyone. Yesterday we announced 2021 GAAP earnings of $2.63 per share compared to $2.47 per share in 2020. On an adjusted basis, which excludes impact of temperatures and non-recurring adjustments, earnings per share increased 7% from 2020. Looking at year-over-year, the increases in 2021 were driven by higher revenue requirements, primarily due to increasing rate base at our Wisconsin and Iowa Utilities and higher electric sales due to strong demand from commercial, industrial customers and the impacts of warmer summer temperatures. These favorable drivers were partially offset by higher depreciation and lower allowance for funds used during construction.
Our temperature normalized retail electric sales grew 3% in 2021 when compared to 2020, primarily driven by a resurgence of our commercial and industrial customers as our state economies have strengthened from the worst impacts of the pandemic in 2020. This recovery was more robust in 2021 than initially forecasted, led by stronger industrial sales resulting in total commercial and industrial sales levels for the year, roughly 1% higher than 2019 levels. As customers across our service territories have gradually been returning to their workplaces, we have seen some decline in residential sales. However, residential sales remain modestly higher than 2019 levels.
The strong sales we experienced in 2021 were bolstered by a great year from our economic development efforts, as our team was able to assist with several key industrial customer additions and expansions, ultimately adding about 75 megawatts of load to our system. Additionally, we saw one of the strongest years of incremental customer growth in the past decade. We are announcing an update to our capital expenditure plans for 2022 through 2025. Our new plan is summarized on Slide 6 of our earnings presentation.
There are two primary drivers for the updated plans. The first relates to recent progress made with our solar equipment suppliers that will allow us to receive equipment and materials earlier than previously anticipated. These efforts have allowed us to pull forward approximately $300 million of renewable expenditures into 2022. This enables us to complete these clean energy investments earlier than planned with 325 megawatts now scheduled to go into service in 2022 for our Wisconsin customers. The balance of our previously announced solar and battery projects are expected to go in service in 2023 and 2024.
The second driver of the updated capital expenditure plans involves accelerating clean energy investments into 2023 through 2025, to address capacity needs resulting from MISO's proposed seasonal resource adequacy construct. For those who may not be familiar, MISO has proposed to a credit generation capacity on a seasonal basis under this new construct versus the current state where capacity is accredited on an annual basis. The additive investments included in our updated capital expenditure plans will help satisfy our anticipated seasonal capacity requirements and support reliability for our customers.
Our capital expenditure plans also continue to include investments to replace the capacity from the anticipated exercise of options by WEC Energy and MG&E to purchase a portion of our West Riverside natural gas facility. We anticipate making a certificate of authority filing with the PSCW in the first half of this year for additional capacity resources to replace the capacity expected to be lost with the exercise of these options. We plan to share more details about these resources as we get closer to making that filing.
Turning to this year's earnings guidance with the updates to our capital expenditures plans, we are increasing our 2022 earnings guidance and remain well-positioned for consistent 5% to 7% earnings growth going forward. The midpoint of our updated guidance range is $2.74 per share, which represents a 6% increase over 2021 adjusted earnings. The expected drivers of this increase in earnings include higher earnings on increasing capital investments and higher AFUDC benefits from our solar projects under construction. More details on our 2022 earnings guidance are provided on Slide 7 of our earnings presentation.
In 2002, we estimate a consolidated effective tax rate of 4% with substantial production tax credits generated by our large wind portfolio, helping us maintain the low effective tax rate for the upcoming year and several more years to come. The benefits from these production tax credits are passed on to our electric customers to help manage customer bills and therefore are largely earnings neutral.
Moving on to the financing plans for 2022, we plan to issue long-term debt of up to $1.4 billion in total for WPL and Alliant Energy Finance. The proceeds from the new debt will be used largely to finance investments in solar projects as well as to refinance $625 million of debt maturities in 2022. We also expect to receive approximately $25 million of new common equity under our DRIP plan in 2022.
Lastly, we have included this year's key regulatory initiatives on Slide 8 related to our customer investments, in Wisconsin, we anticipate a decision on our approval request for 414 megawatts of solar in the first half of this year. And in Iowa, our advance ratemaking filing for 475 megawatts of solar and battery is progressing as expected. The Iowa Utilities Board issued a procedural schedule last month which can be found on Slide 9. We anticipate a decision on this advance ratemaking filing in the second half of this year.
In Wisconsin, we also filed a joint application for the sale of a portion of our West Riverside natural gas generating facility to WEC Energy and MG&E at the end of January. We anticipate a decision on this application in either late 2022 or early 2023. These regulatory initiatives are an important part of executing our strategy, and we are thankful for the continued constructive relationships with our regulators in both of our state jurisdictions.
As we conclude another successful year with solid financial results and constructive regulatory outcomes, I want to express my optimism for the year ahead. We've demonstrated the flexibility of our capex plan to shift quickly due to opportunities in the solar projects supply chain. We have regulatory certainty for the next couple of years with no major rate reviews planned, and we have dedicated and talented employees working hard every day to serve our customers and shareowners.
We appreciate your continued support of our company and look forward to meeting with many of you virtually and in person in the coming months. As always, we will make our Investor Relation materials available on our website.
At this time, I'll turn the call back over to the operator to facilitate the question-and-answer session.