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United States
Securities and Exchange Commission
Washington, D.C. 20549
Form 10-K
(Mark One)
 
 
Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
For the year ended December 31, 2019
 
Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
 
 
For the transition period from ______________ to ______________
Commission File Number 1-3548
ALLETE, Inc.
(Exact name of registrant as specified in its charter)
Minnesota
 
41-0418150
(State or other jurisdiction of incorporation or organization)
 
(I.R.S. Employer Identification No.)
30 West Superior Street, Duluth, Minnesota 55802-2093
(Address of principal executive offices, including zip code)
(218) 279-5000
(Registrant’s telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading Symbol
Name of each exchange on which registered
Common Stock, without par value
ALE
New York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act:
None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.     Yes     No
 
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes      No
 
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes     No
 
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).     Yes     No
  
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.     
Large Accelerated Filer             Accelerated Filer    
Non-Accelerated Filer             Smaller Reporting Company    
Emerging Growth Company    
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  
 
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     Yes      No
 
The aggregate market value of voting stock held by nonaffiliates on June 28, 2019, was $4,285,299,935.
 
As of February 1, 2020, there were 51,696,497 shares of ALLETE Common Stock, without par value, outstanding.
 
Documents Incorporated By Reference
Portions of the Proxy Statement for the 2020 Annual Meeting of Shareholders are incorporated by reference in Part III.




Index
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


ALLETE, Inc. 2019 Form 10-K
2



Index (Continued)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


ALLETE, Inc. 2019 Form 10-K
3



Definitions

The following abbreviations or acronyms are used in the text. References in this report to “we,” “us” and “our” are to ALLETE, Inc. and its subsidiaries, collectively.
Abbreviation or Acronym
Term
AFUDC
Allowance for Funds Used During Construction - the cost of both debt and equity funds used to finance utility plant additions during construction periods
ALLETE
ALLETE, Inc.
ALLETE Clean Energy
ALLETE Clean Energy, Inc. and its subsidiaries
ALLETE Properties
ALLETE Properties, LLC and its subsidiaries
ALLETE South Wind
ALLETE South Wind, LLC
ALLETE Transmission Holdings
ALLETE Transmission Holdings, Inc.
ArcelorMittal
ArcelorMittal USA, Inc.
ATC
American Transmission Company LLC
Basin
Basin Electric Power Cooperative
Bison
Bison Wind Energy Center
BNI Energy
BNI Energy, Inc. and its subsidiary
Boswell
Boswell Energy Center
Camp Ripley
Camp Ripley Solar Array
CIP
Conservation Improvement Program
Cliffs
Cleveland-Cliffs Inc.
Company
ALLETE, Inc. and its subsidiaries
DC
Direct Current
EIS
Environmental Impact Statement
EPA
United States Environmental Protection Agency
ESOP
Employee Stock Ownership Plan
FASB
Financial Accounting Standards Board
FERC
Federal Energy Regulatory Commission
Form 8-K
ALLETE Current Report on Form 8-K
Form 10-K
ALLETE Annual Report on Form 10-K
Form 10-Q
ALLETE Quarterly Report on Form 10-Q
GAAP
Generally Accepted Accounting Principles in the United States of America
GHG
Greenhouse Gases
GNTL
Great Northern Transmission Line
Invest Direct
ALLETE’s Direct Stock Purchase and Dividend Reinvestment Plan
IRP
Integrated Resource Plan
Item ___
Item ___ of this Form 10-K
kV
Kilovolt(s)
kW / kWh
Kilowatt(s) / Kilowatt-hour(s)
Laskin
Laskin Energy Center
Manitoba Hydro
Manitoba Hydro-Electric Board
MBtu
Million British thermal units
Minnesota Power
An operating division of ALLETE, Inc.
Minnkota Power
Minnkota Power Cooperative, Inc.
MISO
Midcontinent Independent System Operator, Inc.
Montana-Dakota Utilities
Montana-Dakota Utilities Co., a subsidiary of MDU Resources Group, Inc.
Moody’s
Moody’s Investors Service, Inc.

ALLETE, Inc. 2019 Form 10-K
4



Definitions (continued)
Abbreviation or Acronym
Term
MPCA
Minnesota Pollution Control Agency
MPUC
Minnesota Public Utilities Commission
MW / MWh
Megawatt(s) / Megawatt-hour(s)
NDPSC
North Dakota Public Service Commission
NERC
North American Electric Reliability Corporation
Nobles 2
Nobles 2 Power Partners, LLC
NOL
Net Operating Loss
NOX
Nitrogen Oxides
Northern States Power
Northern States Power Company, a subsidiary of Xcel Energy Inc.
Northshore Mining
Northshore Mining Company, a wholly-owned subsidiary of Cliffs
Note ___
Note ___ to the consolidated financial statements in this Form 10-K
NTEC
Nemadji Trail Energy Center
NYSE
New York Stock Exchange
Oliver Wind I
Oliver Wind I Energy Center
Oliver Wind II
Oliver Wind II Energy Center
Palm Coast Park District
Palm Coast Park Community Development District in Florida
PolyMet
PolyMet Mining Corp.
PPA / PSA
Power Purchase Agreement / Power Sales Agreement
PPACA
Patient Protection and Affordable Care Act of 2010
PSCW
Public Service Commission of Wisconsin
RSOP
Retirement Savings and Stock Ownership Plan
SEC
Securities and Exchange Commission
S&P
S&P Global Ratings
Silver Bay Power
Silver Bay Power Company, a wholly-owned subsidiary of Cliffs
SO2
Sulfur Dioxide
Square Butte
Square Butte Electric Cooperative, a North Dakota cooperative corporation
SWL&P
Superior Water, Light and Power Company
Taconite Harbor
Taconite Harbor Energy Center
Taconite Ridge
Taconite Ridge Energy Center
Tenaska
Tenaska Energy, Inc. and Tenaska Energy Holdings, LLC
TCJA
Tax Cuts and Jobs Act of 2017 (Public Law 115-97)
Tonka Water
Tonka Equipment Company
Town Center District
Town Center at Palm Coast Community Development District in Florida
United Taconite
United Taconite LLC, a wholly-owned subsidiary of Cliffs
UPM Blandin
UPM, Blandin paper mill owned by UPM-Kymmene Corporation
U.S.
United States of America
U.S. Water Services
U.S. Water Services, Inc. and its subsidiaries
USS Corporation
United States Steel Corporation
WTG
Wind Turbine Generator

ALLETE, Inc. 2019 Form 10-K
5



Forward-Looking Statements

Statements in this report that are not statements of historical facts are considered “forward-looking” and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such forward-looking statements have been made in good faith and are based on reasonable assumptions, there can be no assurance that the expected results will be achieved. Any statements that express, or involve discussions as to, future expectations, risks, beliefs, plans, objectives, assumptions, events, uncertainties, financial performance, or growth strategies (often, but not always, through the use of words or phrases such as “anticipates,” “believes,” “estimates,” “expects,” “intends,” “plans,” “projects,” “likely,” “will continue,” “could,” “may,” “potential,” “target,” “outlook” or words of similar meaning) are not statements of historical facts and may be forward-looking.

In connection with the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, we are providing this cautionary statement to identify important factors that could cause our actual results to differ materially from those indicated in forward-looking statements made by or on behalf of ALLETE in this Form 10-K, in presentations, on our website, in response to questions or otherwise. These statements are qualified in their entirety by reference to, and are accompanied by, the following important factors, in addition to any assumptions and other factors referred to specifically in connection with such forward-looking statements that could cause our actual results to differ materially from those indicated in the forward-looking statements:

our ability to successfully implement our strategic objectives;
global and domestic economic conditions affecting us or our customers;
changes in and compliance with laws and regulations;
changes in tax rates or policies or in rates of inflation;
the outcome of legal and administrative proceedings (whether civil or criminal) and settlements;
weather conditions, natural disasters and pandemic diseases;
our ability to access capital markets, bank financing and other financing sources;
changes in interest rates and the performance of the financial markets;
project delays or changes in project costs;
changes in operating expenses and capital expenditures and our ability to raise revenues from our customers;
the impacts of commodity prices on ALLETE and our customers;
our ability to attract and retain qualified, skilled and experienced personnel;
effects of emerging technology;
war, acts of terrorism and cybersecurity attacks;
our ability to manage expansion and integrate acquisitions;
population growth rates and demographic patterns;
wholesale power market conditions;
federal and state regulatory and legislative actions that impact regulated utility economics, including our allowed rates of return, capital structure, ability to secure financing, industry and rate structure, acquisition and disposal of assets and facilities, operation and construction of plant facilities and utility infrastructure, recovery of purchased power, capital investments and other expenses, including present or prospective environmental matters;
effects of competition, including competition for retail and wholesale customers;
effects of restructuring initiatives in the electric industry;
the impacts on our businesses of climate change and future regulation to restrict the emissions of GHG;
effects of increased deployment of distributed low-carbon electricity generation resources;
the impacts of laws and regulations related to renewable and distributed generation;
pricing, availability and transportation of fuel and other commodities and the ability to recover the costs of such commodities;
our current and potential industrial and municipal customers’ ability to execute announced expansion plans;
real estate market conditions where our legacy Florida real estate investment is located may not improve; and
the success of efforts to realize value from, invest in, and develop new opportunities.

Additional disclosures regarding factors that could cause our results or performance to differ from those anticipated by this report are discussed in Part 1, Item 1A under the heading “Risk Factors” of this Form 10-K. Any forward-looking statement speaks only as of the date on which such statement is made, and we undertake no obligation to update any forward‑looking statement to reflect events or circumstances after the date on which that statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for management to predict all of these factors, nor can it assess the impact of each of these factors on the businesses of ALLETE or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. Readers are urged to carefully review and consider the various disclosures made by ALLETE in this Form 10-K and in other reports filed with the SEC that attempt to identify the risks and uncertainties that may affect ALLETE’s business.


ALLETE, Inc. 2019 Form 10-K
6



Part I

Item 1. Business

Regulated Operations includes our regulated utilities, Minnesota Power and SWL&P, as well as our investment in ATC, a Wisconsin-based regulated utility that owns and maintains electric transmission assets in portions of Wisconsin, Michigan, Minnesota and Illinois. Minnesota Power provides regulated utility electric service in northeastern Minnesota to approximately 145,000 retail customers. Minnesota Power also has 15 non-affiliated municipal customers in Minnesota. SWL&P is a Wisconsin utility and a wholesale customer of Minnesota Power. SWL&P provides regulated utility electric, natural gas and water service in northwestern Wisconsin to approximately 15,000 electric customers, 13,000 natural gas customers and 10,000 water customers. Our regulated utility operations include retail and wholesale activities under the jurisdiction of state and federal regulatory authorities. (See Note 4. Regulatory Matters.)

ALLETE Clean Energy focuses on developing, acquiring, and operating clean and renewable energy projects. ALLETE Clean Energy currently owns and operates, in five states, approximately 660 MW of nameplate capacity wind energy generation that is contracted under PSAs of various durations. In addition, ALLETE Clean Energy currently has approximately 380 MW of wind energy facilities under construction that it will own and operate with long-term PSAs in place. ALLETE Clean Energy also engages in the development of wind energy facilities to operate under long-term PSAs or for sale to others upon completion.

U.S. Water Services provided integrated water management for industry by combining chemical, equipment, engineering and service for customized solutions to reduce water and energy usage, and improve efficiency. On March 26, 2019, the Company sold U.S. Water Services to a subsidiary of Kurita Water Industries Ltd. pursuant to a stock purchase agreement for approximately $270 million in cash, net of transaction costs and cash retained.

Corporate and Other is comprised of BNI Energy, our coal mining operations in North Dakota, our investment in Nobles 2, a 49 percent equity interest in the entity that will own and operate a 250 MW wind energy facility in southwestern Minnesota, ALLETE Properties, our legacy Florida real estate investment, other business development and corporate expenditures, unallocated interest expense, a small amount of non-rate base generation, approximately 4,000 acres of land in Minnesota, and earnings on cash and investments.

ALLETE is incorporated under the laws of Minnesota. Our corporate headquarters are in Duluth, Minnesota. Statistical information is presented as of December 31, 2019, unless otherwise indicated. All subsidiaries are wholly-owned unless otherwise specifically indicated. References in this report to “we,” “us” and “our” are to ALLETE and its subsidiaries, collectively.
Year Ended December 31
2019

2018

2017

 
 
 
 
Consolidated Operating Revenue – Millions (a)(b)

$1,240.5


$1,498.6


$1,419.3

 
 
 
 
Percentage of Consolidated Operating Revenue
 
 
 
Regulated Operations
84
%
71
%
75
%
ALLETE Clean Energy (a)
5
%
11
%
6
%
U.S. Water Services (b)
3
%
11
%
11
%
Corporate and Other
8
%
7
%
8
%
 
100
%
100
%
100
%
(a)
Includes the sale of a wind energy facility to Montana-Dakota Utilities for $81.1 million in 2018.
(b)
ALLETE sold U.S. Water Services in the first quarter of 2019.

For a detailed discussion of results of operations and trends, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations. For business segment information, see Note 1. Operations and Significant Accounting Policies and Note 14. Business Segments.



ALLETE, Inc. 2019 Form 10-K
7



REGULATED OPERATIONS

Electric Sales / Customers
Regulated Utility Kilowatt-hours Sold
 
 
 
 
 
 
Year Ended December 31
2019

%
2018

%
2017

%
Millions
 
 
 
 
 
 
Retail and Municipal
 
 
 
 
 
 
Residential
1,130

8
1,140

8
1,096

7
Commercial
1,390

10
1,426

10
1,420

10
Industrial
7,277

54
7,261

50
7,327

50
Municipal
672

5
798

5
799

5
Total Retail and Municipal
10,469

77
10,625

73
10,642

72
Other Power Suppliers
3,185

23
3,953

27
4,039

28
Total Regulated Utility Kilowatt-hours Sold
13,654

100
14,578

100
14,681

100

Industrial Customers. In 2019, industrial customers represented 54 percent of total regulated utility kWh sales. Our industrial customers are primarily in the taconite mining, paper, pulp and secondary wood products, and pipeline industries.
Industrial Customer Kilowatt-hours Sold
 
 
 
 
 
 
Year Ended December 31
2019

%
2018

%
2017

%
Millions
 
 
 
 
 
 
Taconite
5,039

69
5,039

69
4,930

67
Paper, Pulp and Secondary Wood Products
1,014

14
987

14
1,104

15
Pipelines and Other Industrial
1,224

17
1,235

17
1,293

18
Total Industrial Customer Kilowatt-hours Sold
7,277

100
7,261

100
7,327

100

Six taconite facilities served by Minnesota Power made up approximately 80 percent of 2018 iron ore pellet production in the U.S. according to data from the Minnesota Department of Revenue 2019 Mining Tax Guide. Sales to taconite customers represented 5,039 million kWh, or 69 percent of total industrial customer kWh sales in 2019. Taconite, an iron‑bearing rock of relatively low iron content, is abundantly available in northern Minnesota and an important domestic source of raw material for the steel industry. Taconite processing plants use large quantities of electric power to grind the iron-bearing rock, and agglomerate and pelletize the iron particles into taconite pellets.

Minnesota Power’s taconite customers are capable of producing approximately 41 million tons of taconite pellets annually. Taconite pellets produced in Minnesota are primarily shipped to North American steel making facilities that are part of the integrated steel industry. Steel produced from these North American facilities is used primarily in the manufacture of automobiles, appliances, pipe and tube products for the gas and oil industry, and in the construction industry. Historically, less than 10 percent of Minnesota taconite production has been exported outside of North America.

There has been a general historical correlation between U.S. steel production and Minnesota taconite production. The American Iron and Steel Institute, an association of North American steel producers, reported that U.S. raw steel production operated at approximately 80 percent of capacity in 2019 (78 percent in 2018 and 74 percent in 2017). The World Steel Association, an association of over 160 steel producers, national and regional steel industry associations, and steel research institutes representing approximately 85 percent of world steel production, projected U.S. steel consumption in 2020 will increase by approximately one percent compared to 2019.

ALLETE, Inc. 2019 Form 10-K
8



REGULATED OPERATIONS (Continued)
Industrial Customers (Continued)

The following table reflects Minnesota Power’s taconite customers’ production levels for the past ten years:
Minnesota Power Taconite Customer Production
Year
 
Tons (Millions)
2019*
 
37
2018
 
39
2017
 
38
2016
 
28
2015
 
31
2014
 
39
2013
 
37
2012
 
39
2011
 
39
2010
 
35
Source: Minnesota Department of Revenue 2019 Mining Tax Guide for years 2010 - 2018.
* Preliminary data from the Minnesota Department of Revenue.

Minnesota Power’s taconite customers may experience annual variations in production levels due to such factors as economic conditions, short-term demand changes or maintenance outages. We estimate that a one million ton change in Minnesota Power’s taconite customers’ production would impact our annual earnings per share by approximately $0.04, net of expected power marketing sales at current prices. Changes in wholesale electric prices or customer contractual demand nominations could impact this estimate. Minnesota Power proactively sells power in the wholesale power markets that is temporarily not required by industrial customers to optimize the value of its generating facilities. Long-term reductions in taconite production or a permanent shut down of a taconite customer may lead Minnesota Power to file a general rate case to recover lost revenue.

In addition to serving the taconite industry, Minnesota Power serves a number of customers in the paper, pulp and secondary wood products industry, which represented 1,014 million kWh, or 14 percent of total industrial customer kWh sales in 2019. Minnesota Power also has agreements to provide steam for two of its paper and pulp customers for use in the customers’ operations. The four major paper and pulp mills we serve reported operating at similar levels in 2019 compared to 2018.

Large Power Customer Contracts. Minnesota Power has eight Large Power Customer contracts, each serving requirements of 10 MW or more of customer load. The customers consist of six taconite facilities and four paper and pulp mills. Certain facilities have common ownership and are served under combined contracts.

Large Power Customer contracts require Minnesota Power to have a certain amount of generating capacity available. In turn, each Large Power Customer is required to pay a minimum monthly demand charge that covers the fixed costs associated with having this capacity available to serve the customer, including a return on common equity. Most contracts allow customers to establish the level of megawatts subject to a demand charge on a four-month basis and require that a portion of their megawatt needs be committed on a take-or-pay basis for at least a portion of the term of the agreement. In addition to the demand charge, each Large Power Customer is billed an energy charge for each kWh used that recovers the variable costs incurred in generating electricity. Five of the Large Power Customer contracts have interruptible service which provides a discounted demand rate in exchange for the ability to interrupt the customers during system emergencies. Minnesota Power also provides incremental production service for customer demand levels above the contractual take-or-pay levels. There is no demand charge for this service and energy is priced at an increment above Minnesota Power’s cost. Incremental production service is interruptible.


ALLETE, Inc. 2019 Form 10-K
9



REGULATED OPERATIONS (Continued)
Large Power Customer Contracts (Continued)

All contracts with Large Power Customers continue past the contract termination date unless the required advance notice of cancellation has been given. The required advance notice of cancellation varies from two to four years. Such contracts minimize the impact on earnings that otherwise would result from significant reductions in kWh sales to such customers. Large Power Customers are required to take all of their purchased electric service requirements from Minnesota Power for the duration of their contracts. The rates and corresponding revenue associated with capacity and energy provided under these contracts are subject to change through the same regulatory process governing all retail electric rates. (See Regulatory Matters – Electric Rates.)

Minnesota Power, as permitted by the MPUC, requires its taconite-producing Large Power Customers to pay weekly for electric usage based on monthly energy usage estimates. These customers receive estimated bills based on Minnesota Power’s estimate of the customer’s energy usage, forecasted energy prices and fuel adjustment clause estimates. Minnesota Power’s taconite‑producing Large Power Customers have generally predictable energy usage on a week-to-week basis and any differences that occur are trued-up the following month.

Contract Status for Minnesota Power Large Power Customers
As of December 31, 2019
Customer
Industry
Location
Ownership
Earliest
Termination Date
ArcelorMittal – Minorca Mine
Taconite
Virginia, MN
ArcelorMittal S.A.
December 31, 2025
Hibbing Taconite Co. (a)
Taconite
Hibbing, MN
62.3% ArcelorMittal S.A.
23.0% Cliffs
14.7% USS Corporation
December 31, 2023
United Taconite and Northshore Mining
Taconite
Eveleth, MN and Babbitt, MN
Cliffs
December 31, 2026
USS Corporation
(USS – Minnesota Ore) (a)(b)
Taconite
Mt. Iron, MN and Keewatin, MN
USS Corporation
December 31, 2023
Boise, Inc. (a)
Paper
International Falls, MN
Packaging Corporation of America
December 31, 2023
UPM Blandin
Paper
Grand Rapids, MN
UPM-Kymmene Corporation
December 31, 2029
Verso Duluth Mill
Paper and Pulp
Duluth, MN
Verso Corporation
December 31, 2024
Sappi Cloquet LLC (a)
Paper and Pulp
Cloquet, MN
Sappi Limited
December 31, 2023
(a)
The contract will terminate four years from the date of written notice from either Minnesota Power or the customer. No notice of contract cancellation has been given by either party. Thus, the earliest date of cancellation is December 31, 2023.
(b)
USS Corporation owns both the Minntac Plant in Mountain Iron, MN, and the Keewatin Taconite Plant in Keewatin, MN.

Residential and Commercial Customers. In 2019, residential and commercial customers represented 18 percent of total regulated utility kWh sales.

Municipal Customers. In 2019, municipal customers represented five percent of total regulated utility kWh sales. All of the municipal contracts include a termination clause requiring a three-year notice to terminate.

Minnesota Power’s wholesale electric contracts with 15 non-affiliated municipal customers in Minnesota have termination dates ranging from 2024 through at least 2032, with a majority of contracts effective through at least 2024. (See Note 4. Regulatory Matters.)

The contract with another municipal customer expired on June 30, 2019. Minnesota Power historically provided approximately 29 MW of average monthly demand to this customer.


ALLETE, Inc. 2019 Form 10-K
10



REGULATED OPERATIONS (Continued)

Other Power Suppliers. The Company also enters into off-system sales with Other Power Suppliers. These sales are at market‑based prices into the MISO market on a daily basis or through bilateral agreements of various durations.

Our PSAs are detailed in Note 9. Commitments, Guarantees and Contingencies, with additional disclosure provided in the following paragraphs.

Basin PSAs. Minnesota Power has an agreement to sell 100 MW of capacity and energy to Basin for a ten-year period which expires in April 2020. The capacity charge is based on a fixed monthly schedule with a minimum annual escalation provision. The energy charge is based on a fixed monthly schedule and provides for annual escalation based on the cost of fuel. The agreement also allows Minnesota Power to recover a pro rata share of increased costs related to emissions that occur during the last five years of the contract. Minnesota Power has two additional agreements to sell capacity to Basin at fixed prices. (See Note 9. Commitments, Guarantees and Contingencies.)

Minnkota Power PSA. Minnesota Power has a PSA with Minnkota Power where Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, it sold approximately 28 percent to Minnkota Power in 2019 (28 percent in 2018 and in 2017). (See Power Supply – Long-Term Purchased Power.)

Silver Bay Power PSA. In 2016, Minnesota Power and Silver Bay Power entered into a PSA through 2031. Silver Bay Power supplies approximately 90 MW of load to Northshore Mining, an affiliate of Silver Bay Power, which had previously been served predominately through self-generation by Silver Bay Power. Starting in 2016, Minnesota Power supplied Silver Bay Power with at least 50 MW of energy and Silver Bay Power had the option to purchase additional energy from Minnesota Power as it transitioned away from self-generation. In the third quarter of 2019, Silver Bay Power ceased self-generation and Minnesota Power began supplying the full energy requirements for Silver Bay Power.

Seasonality

The operations of our industrial customers, which make up a large portion of our electric sales, are not typically subject to significant seasonal variations. (See Electric Sales / Customers.) As a result, Minnesota Power is generally not subject to significant seasonal fluctuations in electric sales; however, Minnesota Power and SWL&P electric and natural gas sales to other customers may be affected by seasonal differences in weather. In general, peak electric sales occur in the winter and summer months with fewer electric sales in the spring and fall months. Peak sales of natural gas generally occur in the winter months. Additionally, our regulated utilities have historically generated fewer sales and less revenue when weather conditions are milder in the winter and summer.

Power Supply

In order to meet its customers’ electric requirements, Minnesota Power utilizes a mix of its own generation and purchased power. As of December 31, 2019, Minnesota Power’s generating capability is primarily coal-fired, but also includes wind energy, hydroelectric, natural gas-fired, biomass co-fired and solar generation. Purchased power primarily consists of long-term coal, wind and hydro PPAs as well as market purchases. The following table reflects Minnesota Power’s generating capabilities as of December 31, 2019, and total electrical supply for 2019. Minnesota Power had an annual net peak load of 1,573 MW on November 11, 2019.

ALLETE, Inc. 2019 Form 10-K
11



REGULATED OPERATIONS (Continued)
Power Supply (Continued)
 
 
 
 
 
Year Ended
 
Unit
Year
Net
 
December 31, 2019
Regulated Utility Power Supply
No.
Installed
Capability
 
Generation and Purchases
 
 
 
MW
 
MWh
%
Coal-Fired
 
 
 
 
 
 
Boswell Energy Center (a)
3
1973
355

 
 
 
in Cohasset, MN
4
1980
468

(b)
 
 
 
 
 
823

 
4,160,011

29.6
Taconite Harbor Energy Center
1
1957
75

 
 
 
in Schroeder, MN
2
1957
75

 
 
 
 
 
 
150

(c)

Total Coal-Fired
 
 
973

 
4,160,011

29.6
Biomass Co-Fired / Natural Gas
 
 
 
 
 
 
Hibbard Renewable Energy Center in Duluth, MN
3 & 4
1949, 1951
62

 
21,846

0.2
Laskin Energy Center in Hoyt Lakes, MN
1 & 2
1953
110

 
19,454

0.1
Total Biomass Co-Fired / Natural Gas
 
 
172

 
41,300

0.3
Hydro (d)
 
 
 
 
 
 
Group consisting of ten stations in MN
Multiple
Multiple
120

 
643,771

4.6
Wind (e)
 
 
 
 
 
 
Taconite Ridge Energy Center in Mt. Iron, MN
Multiple
2008
25

 
46,808

0.3
Bison Wind Energy Center in Oliver and Morton Counties, ND
Multiple
2010-2014
497

 
1,571,045

11.2
Total Wind
 
 
522

 
1,617,853

11.5
Solar
 
 
 
 
 
 
Camp Ripley Solar Array near Little Falls, MN
Multiple
2016
10

 
14,069

0.1
Total Generation
 
 
1,797

 
6,477,004

46.1