Intangible assets (Tables)

12 Months Ended

Mar. 31, 2026

Disclosure of detailed information about intangible assets [abstract]

Summary of Changes in Intangible Assets and Goodwill


	Computer software			Customer contracts#		Customer relationship*		Development rights		Other intangible assets		Carbon credit rights		Goodwill			Intangible asset under development			Total intangible assets
	(INR)			(INR)		(INR)		(INR)		(INR)		(INR)		(INR)			(INR)			(INR)
Cost
As at April 1, 2023		622			32,592		-		36		7		—		11,596			151			45,004
Additions during the year		180			—		—		—		—		626		—			30			836
Transfer/Capitalised during the year		124			—		—		—		—		—		—			(124	)		-
As at March 31, 2024		926			32,592		-		36		7		626		11,596			57			45,840
Additions during the year		-			—		—		—		—		—		—			110			110
Assets held for sale		(29	)		—		—		—		—		—		—			—			(29	)
Disposals and adjustments during the year		(41	)		-		-		-		-		-		-			-			(41	)
Transfer/Capitalised during the year		76			—		—		—		—		—		—			(76	)		-
As at March 31, 2025		932			32,592		-		36		7		626		11,596			91			45,880
Additions during the year		257			-		-		—		—		—		—			—			257
Acquisition through business combination (refer Note 52)		589			-		1,005		—		—		—		5,531			—			7,125
Disposals and adjustments during the year		(46	)		—		—		—		—		—		(37	)		(62	)		(145	)
Transfer/Capitalised during the year		7			—		—		—		—		—		—			(7	)		-
Exchange differences		8			-		76								471			-			555
As at March 31, 2026		1,747			32,592		1,081		36		7		626		17,561			22			53,672

Accumulated amortisation
As at April 1, 2023		250			6,154		-		5		0		—		—			0			6,409
Charge for the year (refer Note 32)		136			1,348		-		1		0		—		—			0			1,485
Capitalised during the year		—			63		-		—		—		—		—			—			63
As at March 31, 2024		386			7,565		-		6		0		—		—			0			7,957
Charge for the year (refer Note 32)		48			1,416				0		1		167		—			0			1,632
Assets held for sale		(20	)		—		—		—		—		—		—			—			(20	)
Capitalised during the year		94			—		—		—		—		—		—			—			94
As at March 31, 2025		508			8,981		-		6		1		167		—			0			9,663
Charge for the year (refer Note 32)		163			1,415		154		1		—		144		—			—			1,877
Impairment for the year (refer Note 32)		—			—		—		—		—		160		812			—			972
Capitalised during the year		106			—		—		—		—		—		—			—			106
Disposals and adjustments during the year		(32	)										—								(32	)
As at March 31, 2026		745			10,396		154		7		1		471		812			0			12,586

Net book value
As at April 1, 2024 (INR)		540			25,027		-		30		7		626		11,596			57			37,883
As at March 31, 2025 (INR)		424			23,611		-		30		6		459		11,596			91			36,217
As at March 31, 2026 (INR)		1,002			22,196		927		29		6		155		16,749			22			41,086
As at March 31, 2026 (USD)		11			237		10		0		0		2		179			0			438

# Remaining life of customer contracts ranges from 12 to 18 years as on March 31, 2026 (March 31, 2025: 13 to 19 years, March 31, 2024: 14 to 20 years).

* Remaining life of customer relationship is 9 years.

Summary of Break-Up of Carrying Value of Goodwill and Intangible Assets

Below is the break-up of carrying value of goodwill allocated to each cash generating units (CGU)/group of CGU:


		As at March 31,
Group of CGU / individual CGU	Segment	2026		2025

Ostro Energy Group	Generation and sale of renewable power		9,091		9,903
ReNew Vayu Urja	Generation and sale of renewable power		756		756
Prathamesh Solarfarms	Generation and sale of renewable power		428		428
3E NV	Software solutions (included in non reportable segment)		6,002		-
	Software solutions (included in non reportable segment)
Others*	Generation and sale of renewable power		472		509
			16,749		11,596

* includes amount allocated against multiple CGUs and the amount allocated to each CGU is not material.

Summary of goodwill impairment test and estimated value in use after adjusting the carrying values of assets and was more than carrying value of goodwill

For all other CGUs/ Group of CGUs, the estimated recoverable value was more than their respective carrying values, by the following amounts on the valuation dates:


		As at March 31,
Group of CGU / individual CGU	Segment	2026		2025

Ostro Energy Group1	Generation and sale of renewable power		-		5,615
ReNew Vayu Urja2	Generation and sale of renewable power		814		1,527
Prathamesh Solarfarms3	Generation and sale of renewable power		813		970
3E NV4	Software solutions (included in non reportable segment)	-		Not Applicable
Others5	Generation and sale of renewable power		1,529		3,220

(1)

During the year ended 31 March 2026, the Group recognized an impairment loss of INR 812, as the carrying amount exceeded its recoverable value of INR 65,090. The impairment arose as the cash flows from this Group of CGU are expected to be generated only for a finite period of time. With the passage of time, the reduction in expected future cash flows coupled with some changes in key assumptions, triggered this impairment. The Group engaged external specialists to assist in determining (a) future PLFs and (b) discount rates and computation of VIU., The Group has applied a discount rate of 12.71% (March 31, 2025: 12.15%), and PLF of 26.17% (March 31, 2025: 26.27%). Increase in discount rate by 0.5% or a decrease in PLF by 0.5% would lead to a decrease in the recoverable value of the CGU by INR 2,312 and INR 1,565 respectively.

(2)

The Group has currently estimated discount rate of 12.54% (March 31, 2025:13.22%), and PLF of 27.89% (March 31, 2025: 28.23%) in determination of VIU. The Management believes that any reasonably possible change in the key assumptions used in measurement of value in use would not cause the carrying amount of CGU to exceed the value in use.

(3)

The Group has currently estimated discount rate of 12.78% (March 31, 2025: 12.25%), and PLF of 23.45% (March 31, 2025: 22.86%) in determination of VIU. The Management believes that any reasonably possible change in the key assumptions used in measurement of value in use would not cause the carrying amount of CGU to exceed the value in use.

(4)

The recoverable value approximates its carrying value. The Group estimated a revenue growth rate of 16.80% to 25% over the next five years and thereafter a terminal growth rate of 2.2% and a discount rate of 12.70%. A reduction in revenue growth rate by 1% or increase in discount rate by 0.5% would lead to impairment charge of INR 402 and INR 603 respectively.

(5)

The Group has currently estimated discount rates ranging between 12.39% to 14.77% (March 31, 2025: 12.15% to 14.15%), and PLF of 18.13% to 24.62% (March 31, 2025: 18.47% to 25.36%) in determination of VIU. The Management believes that any reasonably possible change in the key assumptions used in measurement of value in use would not cause the carrying amount of each individual CGU to exceed the value in use.