PROPERTY, PLANT AND ACCUMULATED DEPRECIATION

12 Months Ended

Dec. 31, 2014

Notes To Consolidated Financial Statements [Abstract]

Property Plant And Equipment Disclosure [Text Block]

3.       PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION

Utility property, plant and equipment is recorded at original cost. Original cost includes materials, labor, construction overhead and AFUDC for regulated property. The cost of repairs and maintenance, including planned major maintenance activities, is charged to Operating Expenses as incurred.

The following tables summarize the investments in utility property, plant and equipment by asset category:

NU		As of December 31,
(Millions of Dollars)		2014		2013
Distribution - Electric		$	12,495.2	$	11,950.2
Distribution - Natural Gas			2,595.4		2,425.9
Transmission			6,930.7		6,412.5
Generation			1,170.9		1,152.3
Electric and Natural Gas Utility			23,192.2		21,940.9
Other (1)			551.3		508.7
Property, Plant and Equipment, Gross			23,743.5		22,449.6
Less: Accumulated Depreciation
	Electric and Natural Gas Utility		(5,777.8)		(5,387.0)
	Other		(231.8)		(196.2)
Total Accumulated Depreciation			(6,009.6)		(5,583.2)
Property, Plant and Equipment, Net			17,733.9		16,866.4
Construction Work in Progress			913.1		709.8
Total Property, Plant and Equipment, Net		$	18,647.0	$	17,576.2

(1)These assets are primarily comprised of building improvements, computer software, hardware and equipment and telecommunications assets at NU's service company and unregulated companies.

	As of December 31,
	2014								2013
			NSTAR								NSTAR
(Millions of Dollars)	CL&P		Electric		PSNH		WMECO		CL&P		Electric		PSNH		WMECO
Distribution	$	5,158.8	$	4,895.5	$	1,696.7	$	784.2	$	4,930.7	$	4,694.7	$	1,608.2	$	756.6
Transmission		3,274.0		1,928.5		789.7		891.0		3,071.9		1,772.3		695.7		826.4
Generation		-		-		1,136.5		34.4		-		-		1,131.2		21.1
Property, Plant and Equipment, Gross		8,432.8		6,824.0		3,622.9		1,709.6		8,002.6		6,467.0		3,435.1		1,604.1
Less: Accumulated Depreciation		(1,928.0)		(1,761.4)		(1,090.0)		(297.4)		(1,804.1)		(1,631.3)		(1,021.8)		(271.5)
Property, Plant and Equipment, Net		6,504.8		5,062.6		2,532.9		1,412.2		6,198.5		4,835.7		2,413.3		1,332.6
Construction Work in Progress		304.9		272.8		102.9		49.1		252.8		208.2		54.3		48.5
Total Property, Plant and Equipment, Net	$	6,809.7	$	5,335.4	$	2,635.8	$	1,461.3	$	6,451.3	$	5,043.9	$	2,467.6	$	1,381.1

Depreciation of utility assets is calculated on a straight-line basisusing composite rates based on the estimated remaining useful lives of the various classes of property (estimated useful life for PSNH distribution). The composite rates are subject to approval by the appropriate state regulatory agency. The composite ratesinclude a cost of removal component, which is collected from customers over the lives of the plant assets and is recognized as a regulatory liability. Depreciation rates are applied to property from the time it is placed in service.

Upon retirement from service, the cost of the utility asset is charged to the accumulated provision for depreciation. The actual incurred removal costs are applied against the related regulatory liability.

The depreciation rates for the various classes of utility property, plant and equipment aggregate to composite rates as follows:

(Percent)	2014		2013		2012
NU	3.0	%	2.8	%	2.5	%
CL&P	2.7		2.5		2.5
NSTAR Electric	3.0		2.9		2.8
PSNH	3.0		3.0		3.0
WMECO	3.3		2.9		3.3

The following table summarizes average useful lives of depreciable assets:
	Average Depreciable Life
(Years)	NU		CL&P		NSTAR Electric		PSNH		WMECO
Distribution		34.9		37.5		32.3		32.3		30.9
Transmission		42.5		39.8		44.0		43.7		49.9
Generation		31.9		-		-		32.1		25.0
Other		14.2		-		-		-		-