REGULATORY MATTERS

Regulation

DTE Electric and DTE Gas are subject to the regulatory jurisdiction of the MPSC, which issues orders pertaining to rates, recovery of certain costs, including the costs of generating facilities and regulatory assets, conditions of service, accounting, and operating-related matters. DTE Electric is also regulated by the FERC with respect to financing authorization and wholesale electric activities. Regulation results in differences in the application of generally accepted accounting principles between regulated and non-regulated businesses.

The Registrants are unable to predict the outcome of the unresolved regulatory matters discussed herein. Resolution of these matters is dependent upon future MPSC orders and appeals, which may materially impact the Consolidated Financial Statements of the Registrants.

Regulatory Assets and Liabilities

DTE Electric and DTE Gas are required to record Regulatory assets and liabilities for certain transactions that would have been treated as revenue or expense in non-regulated businesses. Continued applicability of regulatory accounting treatment requires that rates be designed to recover specific costs of providing regulated services and be charged to and collected from customers. Future regulatory changes or changes in the competitive environment could result in the discontinuance of this accounting treatment for Regulatory assets and liabilities for some or all of the Registrants' businesses and may require the write-off of the portion of any Regulatory asset or liability that was no longer probable of recovery through regulated rates. Management believes that currently available facts support the continued use of Regulatory assets and liabilities and that all Regulatory assets and liabilities are recoverable or refundable in the current regulatory environment.

The following are balances and a brief description of the Registrants' Regulatory assets and liabilities at December 31:



	DTE Energy						DTE Electric
	2017			2016			2017			2016
Assets	(In millions)
Recoverable pension and other postretirement costs
Pension	$	2,000		$	2,159		$	1,502		$	1,642
Other postretirement costs	278			286			211			207
Asset retirement obligation	569			613			569			613
Removal costs asset	299			193			299			193
Recoverable Michigan income taxes	213			231			171			187
Deferred environmental costs	75			78			—			—
Unamortized loss on reacquired debt	65			59			46			39
Transitional Reconciliation Mechanism	46			30			46			30
Customer360 deferred costs	45			33			45			33
Recoverable income taxes related to AFUDC equity	41			59			35			53
Other recoverable income taxes	26			57			26			57
Nuclear Performance Evaluation and Review Committee Tracker	22			—			22			—
Accrued PSCR/GCR revenue	17			22			17			19
Other	82			93			66			76
	3,778			3,913			3,055			3,149
Less amount included in Current Assets	(55		)	(42		)	(50		)	(36		)
	$	3,723		$	3,871		$	3,005		$	3,113



	DTE Energy						DTE Electric
	2017			2016			2017			2016
Liabilities	(In millions)
Refundable federal income taxes	$	2,384		$	—		$	1,946		$	—
Removal costs liability	265			266			—			—
Renewable energy	112			145			112			145
Negative other postretirement offset	80			56			67			55
Negative pension offset	21			36			—			—
Fermi 2 refueling outage	15			27			15			27
Refundable self-implemented rates	2			27			2			27
Other	14			32			12			2
	2,893			589			2,154			256
Less amount included in Current Liabilities	(18		)	(34		)	(17		)	(27		)
	$	2,875		$	555		$	2,137		$	229

As noted below, certain Regulatory assets for which costs have been incurred have been included (or are expected to be included, for costs incurred subsequent to the most recently approved rate case) in DTE Electric's or DTE Gas' rate base, thereby providing a return on invested costs (except as noted). Certain other regulatory assets are not included in rate base but accrue recoverable carrying charges until surcharges to collect the assets are billed. Certain Regulatory assets do not result from cash expenditures and therefore do not represent investments included in rate base or have offsetting liabilities that reduce rate base.

ASSETS

•

Recoverable pension and other postretirement costs — Accounting standards for pension and other postretirement benefit costs require, among other things, the recognition in Other comprehensive income of the actuarial gains or losses and the prior service costs that arise during the period but that are not immediately recognized as components of net periodic benefit costs. DTE Electric and DTE Gas record the impact of actuarial gains or losses and prior service costs as a Regulatory asset since the traditional rate setting process allows for the recovery of pension and other postretirement costs. The asset will reverse as the deferred items are amortized and recognized as components of net periodic benefit costs.^(a)


•	Asset retirement obligation — This obligation is for Fermi 2 decommissioning costs. The asset captures the timing differences between expense recognition and current recovery in rates and will reverse over the remaining life of the related plant.^(a)


•	Removal costs asset — Receivable for the recovery of asset removal expenditures in excess of amounts collected from customers.^(a)

•

Recoverable Michigan income taxes — The State of Michigan enacted a corporate income tax resulting in the establishment of state deferred tax liabilities for DTE Energy's utilities. Offsetting Regulatory assets were also recorded as the impacts of the deferred tax liabilities will be reflected in rates as the related taxable temporary differences reverse and flow through current income tax expense.


•	Deferred environmental costs — The MPSC approved the deferral of investigation and remediation costs associated with DTE Gas' former MGP sites. Amortization of deferred costs is over a ten-year period beginning in the year after costs were incurred, with recovery (net of any insurance proceeds) through base rate filings.^(a)


•	Unamortized loss on reacquired debt — The unamortized discount, premium, and expense related to debt redeemed with a refinancing are deferred, amortized, and recovered over the life of the replacement issue.


•	Transitional Reconciliation Mechanism — The MPSC approved the recovery of the deferred net incremental revenue requirement associated with the transition of PLD customers to DTE Electric's distribution system, effective July 1, 2014. Annual reconciliations will be filed and surcharges will be implemented to recover approved amounts.

•

Customer360 deferred costs — The MPSC approved the deferral and amortization of certain costs associated with implementing Customer360, which is an integrated software application that enables improved interface among customer service, billing, meter reading, credit and collections, device management, account management, and retail access. Amortization of deferred costs over a 15-year amortization period began after the billing system was put into operation during the second quarter of 2017.


•	Recoverable income taxes related to AFUDC equity — Accounting standards for income taxes require recognition of a deferred tax liability for the equity component of AFUDC. A regulatory asset is required for the future increase in taxes payable related to the equity component of AFUDC that will be recovered from customers through future rates over the remaining life of the related plant.


•	Other recoverable income taxes — Income taxes receivable from DTE Electric's customers representing the difference in property-related deferred income taxes and amounts previously reflected in DTE Electric's rates. This asset will reverse over the remaining life of the related plant.

•

Nuclear Performance Evaluation and Review Committee Tracker — Deferral and amortization of certain costs associated with oversight and review of DTE Electric's nuclear power generation program, including safety and regulatory compliance, nuclear leadership, nuclear facilities, as well as operation and financial performance, pursuant to the MPSC authorization. The approved five-year amortization period began January 1, 2018, with recovery (net of carrying costs) through base rate filings.


•	Accrued PSCR/GCR revenue — Receivable for the temporary under-recovery of and carrying costs on fuel and purchased power costs incurred by DTE Electric which are recoverable through the PSCR mechanism and temporary under-recovery of and carrying costs on gas costs incurred by DTE Gas which are recoverable through the GCR mechanism.

________________________________________________


(a)	Regulatory assets not earning a return or accruing carrying charges.

LIABILITIES


•	Refundable federal income taxes — DTE Electric and DTE Gas' remeasurement of deferred taxes due to the enactment of the TCJA, which reflects the net impact of the tax rate change on cumulative temporary differences expected to reverse after the effective date of January 1, 2018. Refer to "2017 Tax Reform" section below for additional information.


•	Removal costs liability — The amount collected from customers for the funding of future asset removal activities.


•	Renewable energy — Amounts collected in rates in excess of renewable energy expenditures.

•

Negative other postretirement offset — DTE Electric and DTE Gas' negative other postretirement costs are not included as a reduction to their authorized rates; therefore, DTE Electric and DTE Gas are accruing a Regulatory liability to eliminate the impact on earnings of the negative other postretirement expense accrual. The Regulatory liabilities will reverse to the extent DTE Electric and DTE Gas' other postretirement expense is positive in future years.


•	Negative pension offset — DTE Gas' negative pension costs are not included as a reduction to its authorized rates; therefore, DTE Gas is accruing a Regulatory liability to eliminate the impact on earnings of the negative pension expense accrued. This Regulatory liability will reverse to the extent DTE Gas' pension expense is positive in future years.


•	Fermi 2 refueling outage — Accrued liability for refueling outage at Fermi 2 pursuant to MPSC authorization.


•	Refundable self-implemented rates — Amounts refundable to customers for base rates implemented from August 1, 2016 to December 31, 2016 in excess of amounts authorized in the January 2017 DTE Electric rate order from the MPSC.

2016 Electric Rate Case Filing

DTE Electric filed a rate case with the MPSC on February 1, 2016 requesting an increase in base rates of $344 million based on a projected twelve-month period ending July 31, 2017. On August 1, 2016, DTE Electric self-implemented a base rate increase of $245 million. On January 31, 2017, the MPSC issued an order approving an annual revenue increase of $184 million for service rendered on or after February 7, 2017. The MPSC authorized a return on equity of 10.1%. On April 28, 2017, DTE Electric filed to refund its customers their pro-rata share of the revenue collected through the self-implementation surcharge in effect from August 1, 2016 through February 7, 2017. On September 15, 2017, the MPSC approved a settlement authorizing DTE Electric to refund its customers $38.5 million of the self-implementation surcharge during the months of October through December 2017. DTE Electric has refunded the majority of the settlement liability as of December 31, 2017.

2017 Electric Rate Case Filing

DTE Electric filed a rate case with the MPSC on April 19, 2017 requesting an increase in base rates of $231 million based on a projected twelve-month period ending October 31, 2018. The requested increase in base rates is primarily due to an increase in net plant resulting from infrastructure investments, environmental compliance, and reliability improvement projects. The rate filing also includes projected changes in sales, operation and maintenance expenses, and working capital. The rate filing also requests an increase in return on equity from 10.1% to 10.5%. To mitigate the impact to its customers resulting from ASU No. 2017-07, Compensation — Retirement Benefits (Topic 715), DTE Electric suggested regulatory accounting treatment for the pension and postretirement cost components previously included as capital overhead. If the MPSC adopts DTE Electric's suggestion, the rate request will be reduced. For further discussion of ASU No. 2017-07, see Note 3 to the Consolidated Financial Statements, "New Accounting Pronouncements." On November 1, 2017, DTE Electric self-implemented a base rate increase of $125 million. A final MPSC order in this case is expected by April 2018.

PSCR Proceedings

The PSCR process is designed to allow DTE Electric to recover all of its power supply costs if incurred under reasonable and prudent policies and practices. DTE Electric's power supply costs include fuel and related transportation costs, purchased and net interchange power costs, NO_x and SO₂ emission allowances costs, urea costs, transmission costs, MISO, and other related costs. The MPSC reviews these costs, policies, and practices for prudence in annual plan and reconciliation filings.

2015 PSCR Year — In March 2016, DTE Electric filed its 2015 PSCR reconciliation that included the recovery of approximately $13 million of costs related to the pass through of a billing adjustment associated with a previous MPSC ordered customer refund. On July 12, 2017, the MPSC issued an order that disallowed recovery of this 2015 PSCR billing adjustment pass through of approximately $16 million, inclusive of interest. DTE Electric recorded the impact of the disallowance in the second quarter of 2017 and filed a claim of appeal with the Michigan Court of Appeals in August 2017.

Certificate of Necessity

On July 31, 2017, DTE Electric filed a request for authority to build a 1,100 megawatt natural gas fueled combined cycle generation facility at DTE Electric's Belle River Power Plant. DTE Electric requested the MPSC to issue three CONs for the following: (1) power supplied by the proposed project is needed, (2) the size, fuel type, and other design characteristics of the proposed project represent the most reasonable and prudent means of meeting the power need, and (3) the estimated capital costs of $989 million for the proposed project will be recoverable in rates from DTE Electric's customers. DTE Electric expects an order in this proceeding from the MPSC by April 27, 2018.

2017 Gas Rate Case Filing

DTE Gas filed a rate case with the MPSC on November 22, 2017 requesting an increase in base rates of $85.1 million based on a projected twelve-month period ending September 30, 2019. The requested increase in base rates is primarily due to an increase in net plant. The rate filing also includes projected changes in sales, operations, maintenance expenses, and working capital. The rate filing also requests an increase in return on equity from 10.1% to 10.5%. To mitigate the impact to its customers resulting from ASU No. 2017-07, Compensation — Retirement Benefits (Topic 715), DTE Gas suggested regulatory accounting treatment for the pension and postretirement cost components previously included as capital overhead. If the MPSC adopts DTE Gas' suggestion, the rate request will be reduced. For further discussion of ASU No. 2017-07, see Note 3 to the Consolidated Financial Statements, "New Accounting Pronouncements." A final MPSC order in this case is expected by September 2018.

2017 Tax Reform

On December 27, 2017, the MPSC issued an order to consider changes in the rates of all Michigan rate-regulated utilities to reflect the effects of the federal TCJA. On January 19, 2018, DTE Electric and DTE Gas filed information with the MPSC regarding the potential change in revenue requirements due to the TCJA effective January 1, 2018, and outlined our recommended method to flow the current and deferred tax benefits of those impacts to ratepayers.