Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Line Items]

Summary of Property, Plant, and Equipment

The following is a summary of DPL’s Property, plant and equipment with corresponding composite depreciation rates at December 31, 2015 and 2014:

	December 31,
$ in millions	2015		Composite Rate	2014		Composite Rate
Regulated:
Transmission	$	239.4	3.9%	$	227.5	4.1%
Distribution	1,085.7		5.0%	1,011.7		5.4%
General	65.9		12.4%	62.5		12.4%
Non-depreciable	62.5		N/A	61.6		N/A
Total regulated	1,453.5			1,363.3
Unregulated:
Production / Generation	1,418.7		4.2%	1,354.9		5.4%
Other	17.0		8.1%	16.1		5.5%
Non-depreciable	19.8		N/A	19.8		N/A
Total unregulated	1,455.5			1,390.8
Total property, plant and equipment in service	$	2,909.0	4.6%	$	2,754.1	5.3%

Ownership Interests

DP&L’s undivided ownership interest in such facilities at December 31, 2015, is as follows:

	DP&L Share		DPL Carrying Value
	Ownership (%)	Summer Production Capacity (MW)	Gross Plant In Service ($ in millions)		Accumulated Depreciation ($ in millions)		Construction Work in Process ($ in millions)
Jointly-owned production units
Conesville - Unit 4	16.5	129	$	26	$	4	$	1
Killen - Unit 2	67.0	402	342		29		2
Miami Fort - Units 7 and 8	36.0	368	219		32		6
Stuart - Units 1 through 4	35.0	808	236		19		18
Zimmer - Unit 1	28.1	371	188		44		12
Transmission (at varying percentages)			43		8		—
Total		2,078	$	1,054	$	136	$	39

Changes in the Liability for Generation AROs

Changes in the Liability for Generation AROs

$ in millions
Balance at December 31, 2013	$	24.4
Calendar 2014
Additions	3.6
Accretion expense	0.9
Settlements	(2.0		)
Balance at December 31, 2014	26.9
Calendar 2015
Additions	40.3
Accretion expense	1.9
Settlements	(3.2		)
Balance at December 31, 2015	$	65.9

Changes in the Liability for Transmission and Distribution Asset Removal Costs

Changes in the Liability for Transmission and Distribution Asset Removal Costs

$ in millions
Balance at December 31, 2013	$	115.0
Calendar 2014
Additions	19.6
Settlements	(15.3		)
Balance at December 31, 2014	119.3
Calendar 2015
Additions	24.3
Settlements	(21.8		)
Balance at December 31, 2015	$	121.8

THE DAYTON POWER AND LIGHT COMPANY [Member]

Property, Plant and Equipment [Line Items]

Summary of Property, Plant, and Equipment

The following is a summary of DP&L’s Property, plant and equipment with corresponding composite depreciation rates at December 31, 2015 and 2014:

	December 31,
$ in millions	2015		Composite Rate	2014		Composite Rate
Regulated:
Transmission	$	413.7	2.3%	$	402.4	2.3%
Distribution	1,639.7		3.3%	1,568.0		3.5%
General	96.9		8.4%	116.1		6.7%
Non-depreciable	62.5		N/A	61.6		N/A
Total regulated	2,212.8			2,148.1
Unregulated:
Production / Generation	3,016.8		2.1%	2,957.7		2.4%
Non-depreciable	15.1		N/A	14.9		N/A
Total unregulated	3,031.9			2,972.6
Total property, plant and equipment in service	$	5,244.7	2.6%	$	5,120.7	2.8%

Ownership Interests

DP&L’s undivided ownership interest in such facilities at December 31, 2015, is as follows:

	DP&L Share		DP&L Carrying Value
	Ownership %	Summer Production Capacity (MW)	Gross Plant In Service ($ in millions)		Accumulated Depreciation ($ in millions)		Construction Work in Process ($ in millions)
Jointly-owned production units
Conesville - Unit 4	16.5	129	$	27	$	8	$	1
Killen - Unit 2	67.0	402	655		326		2
Miami Fort - Units 7 and 8	36.0	368	366		171		6
Stuart - Units 1 through 4	35.0	808	772		338		18
Zimmer - Unit 1	28.1	371	1,104		690		12
Transmission (at varying percentages)			99		64		—
Total		2,078	$	3,023	$	1,597	$	39

Changes in the Liability for Generation AROs

Changes in the Liability for Generation AROs

$ in millions
Balance at December 31, 2013	$	19.9
Calendar 2014
Additions	3.6
Accretion expense	1.1
Settlements	(1.7		)
Balance at December 31, 2014	22.9
Calendar 2015
Additions	40.3
Accretion expense	2.1
Settlements	(3.2		)
Balance at December 31, 2015	$	62.1

Changes in the Liability for Transmission and Distribution Asset Removal Costs

Changes in the Liability for Transmission and Distribution Asset Removal Costs

$ in millions
Balance at December 31, 2013	$	115.0
Calendar 2014
Additions	19.6
Settlements	(15.3		)
Balance at December 31, 2014	119.3
Calendar 2015
Additions	24.3
Settlements	(21.8		)
Balance at December 31, 2015	$	121.8