Solar for Hospital Cost and ROI by Size 2026

Hospitals are among the most energy-hungry buildings in India — operation theatres, MRI suites, central air conditioning, sterilisation autoclaves, blood banks, ICUs, and round-the-clock lighting all combine into a load profile that rarely dips below 40% of peak even at 3 a.m. Across the 50-bed to 500-bed range that defines most Indian private hospitals, the energy intensity sits at 12–25 kWh per bed per day, with HT (High Tension) tariffs of ₹8–10 per kWh eating into operating margins month after month. In 2026, rooftop and ground-mount solar has become the single largest non-clinical cost-saver available to hospital boards — payback periods now sit between 4 and 6 years across all four size brackets, with Accelerated Depreciation (AD) pulling that down by a further 40% in Year 1 for CAPEX buyers.

This guide breaks down the cost and ROI of solar across the four hospital size brackets — 50-bed, 100-bed, 250-bed, and 500-bed — with kWp (kilowatt-peak) recommendations, roof area requirements, ₹ savings, financing options, and the NABH (National Accreditation Board for Hospitals) integration constraints that every hospital project manager needs to plan around.

Direct answer. A 50-bed hospital needs ~100 kWp solar at ₹35–40 lakh with 5–6 year payback; a 100-bed needs 200–400 kWp at ₹0.7–1.4 crore with 5-year payback; a 250-bed needs 500 kWp–1 MWp at ₹1.75–4 crore with 4.5–5 year payback; and a 500-bed needs 1–2 MWp at ₹3.5–7.5 crore with 4–5 year payback. AD cuts effective CAPEX by 40% in Year 1, while OPEX/PPA models charge ₹4.50–5/kWh against grid tariffs of ₹8–10/kWh — zero upfront, immediate savings.

If you’re a hospital CFO, administrator, or facilities head sizing a system right now, this post gives you the brackets, the math, and the financing structures in one place. For deeper drill-downs on individual brackets and financing structures, the section links route through to the sister guides.

How Hospital Energy Consumption Scales With Bed Count

Hospital energy consumption is non-linear with bed count — a 500-bed tertiary care facility doesn’t consume exactly 10× a 50-bed nursing home because the central plant load (chillers, central air handling units, sterilisation, central oxygen, MRI/CT imaging, blood bank refrigeration) is largely independent of bed count and dominates the load curve. The per-bed energy intensity therefore rises with hospital category: a 50-bed multi-speciality runs at the lower end (12–15 kWh/bed/day), while a 500-bed tertiary care hospital with full imaging, cath labs, and a transplant unit can hit 22–25 kWh/bed/day.

The Indian Green Building Council’s IGBC Green Healthcare rating benchmarks normal-load hospitals at 18 kWh/bed/day and high-acuity tertiary care at up to 28 kWh/bed/day. These numbers anchor every solar sizing exercise — get the daily kWh wrong and you either over-build (wasted CAPEX) or under-build (leaves savings on the table). For reference, a typical metro-city 100-bed hospital running 24×7 central AC, four OTs, and a CT scanner consumes 2,000–2,400 kWh/day in summer months and 1,400–1,700 kWh/day in mild winter months — a 30–40% seasonal swing that the solar design has to absorb without curtailment.

The four size brackets used across Indian hospital design — 50, 100, 250, and 500 bed — are not arbitrary. They map to regulatory categories under the Clinical Establishments Act and to NABH accreditation tiers. Solar systems must be sized against each bracket’s typical day-load curve, not nameplate connected load, because connected load on a hospital sanctioned-demand certificate routinely overstates actual consumption by 60–80%. The single biggest sizing error we see on inbound hospital enquiries is a quote built off the sanctioned kVA figure rather than the previous-12-months average daytime kWh — that error alone can over-build a system by 30–60% and push payback from 5 years to 9.

The Hospital Solar Sizing Matrix — 4 Size Brackets

This is the framework we use to scope every hospital enquiry — four size brackets, each with a typical daily consumption, kWp recommendation, roof or land requirement, all-in CAPEX, and payback window. The matrix is the starting point of any hospital proposal we issue.

Bracket	Beds	Daily load	Monthly kWh	Solar size	Roof area	All-in CAPEX	Payback (with AD)
Bracket 1 — Nursing home / day-care	50	600–1,250 kWh	18,000–37,500	100 kWp	5,000 sqft	₹35–40 lakh	5–6 yrs
Bracket 2 — Multi-speciality	100	1,200–2,500 kWh	36,000–75,000	200–400 kWp	15,000–30,000 sqft	₹70 lakh–1.4 cr	~5 yrs
Bracket 3 — Tertiary care	250	3,000–6,250 kWh	90,000–1,87,500	500 kWp–1 MWp	30,000–60,000 sqft	₹1.75–4 cr	4.5–5 yrs
Bracket 4 — Super-speciality	500	6,000–12,500 kWh	1,80,000–3,75,000	1–2 MWp	60,000–1,00,000 sqft	₹3.5–7.5 cr	4–5 yrs

Assumptions throughout: HT commercial tariff ₹8–10/kWh, 5.5 peak sun hours, 78% performance ratio, AD claimed at 40% Y1 + 40% Y2 on 80% of CAPEX under Income Tax Act §32, 25-year warranted modules, MNRE-aligned ALMM (Approved List of Models and Manufacturers) tier-1 modules. For the deeper 100-bed walkthrough, see our solar for private hospital — 100-bed playbook.

The matrix has two non-obvious consequences worth flagging upfront. First, the cost per Wp falls as system size grows — a 100 kWp project lands at ₹38–40 per Wp turnkey, while a 1–2 MWp project drops to ₹32–35 per Wp because module procurement, structure fabrication, and inverter unit costs all benefit from scale. Second, the payback shortens by roughly half a year for every step up the bracket, mainly because larger hospitals have higher daytime load share (more 24×7 critical loads, less weekend drop-off) and so absorb a larger fraction of solar generation as direct self-consumption rather than export at low feed-in tariffs.

A common question we get from boards comparing the brackets: “Can we just install the same 100 kWp on day one and add more later?” Technically yes — staged installation is feasible with modular string inverter design — but the cost-per-Wp penalty (a 200 kWp built in two 100 kWp phases costs 8–12% more than one 200 kWp built in one go) means staging only makes sense when load is genuinely uncertain or when phase-2 funding is contingent on phase-1 performance data. For most hospitals with stable historical consumption, sizing once and right is the cleaner economic call.

50-Bed Hospital — 100 kWp Solar Math

A 50-bed hospital — typically a single-speciality nursing home, maternity centre, or day-care surgery facility — runs a daily load of 600–1,250 kWh depending on whether central air conditioning runs 12 or 24 hours and whether it has an imaging suite (X-ray + ultrasound only vs CT/MRI). Most 50-bed facilities operate on an HT 11-kV connection or a high-tariff LT (Low Tension) commercial connection. Sanctioned demand sits in the 60–150 kVA band.

Recommended sizing: 100 kWp. This is the inflection point where the solar system covers 60–70% of daytime load without exporting heavy surplus into a low-feed-in-tariff grid. A 100 kWp rooftop on metal sheet or RCC roof needs roughly 5,000 sqft of unshaded roof area — typical of a single-block hospital with a 2–3 storey footprint.

All-in CAPEX: ₹35–40 lakh (₹35–40 per Wp turnkey, including modules, string inverters, mounting structure, cabling, HT/LT interface, BIS-certified switchgear, fire-rated cables, monitoring SCADA, and NABH-compliant DG-solar synchronisation). Generation: ~1,50,000 kWh/year. At an effective tariff of ₹8.50/kWh, annual gross savings are ₹12.75 lakh — but most 50-bed solar systems are sized to self-consume, not export. Net annual savings post-O&M sit at ₹3.5–4 lakh in the most common case where the hospital only displaces its day-time HT consumption and exports peak summer surplus at the feed-in tariff.

With AD claimed. At 40% AD on 80% of ₹38 lakh in Year 1, the tax-shield equals ₹38 lakh × 0.8 × 0.4 × 0.30 (assuming 30% corporate tax bracket) = ₹3.65 lakh in Year 1. Effective CAPEX drops to ₹34.35 lakh. Adding the ongoing tariff savings, payback lands at 5–6 years.

Variants we see in the 50-bed bracket. Single-speciality eye hospitals and IVF clinics run closer to the 12 kWh/bed/day end and need only 70–80 kWp; multi-speciality nursing homes with 24×7 maternity and a CT scanner sit at 18–22 kWh/bed/day and benefit from the full 100 kWp. Roof type also drives ₹/Wp cost: a flat RCC roof installs at ₹35/Wp, a metal-sheet roof at ₹37/Wp because of additional purlin reinforcement, and a parking canopy structure at ₹42–45/Wp. We recommend most 50-bed hospitals start with a 100 kWp rooftop CAPEX rather than an OPEX/PPA — at this scale, the developer overhead on a PPA structure eats the tariff arbitrage and OPEX rarely beats CAPEX-with-AD on IRR.

100-Bed Hospital — 200–400 kWp Solar Math

The 100-bed bracket is the most common multi-speciality format in tier-2 and tier-3 Indian cities. Daily consumption runs 1,200–2,500 kWh (36,000–75,000 kWh/month), driven by central AC, two to four operation theatres, an ICU of 8–12 beds, dialysis station, blood bank, and one imaging suite (CT or MRI). HT 11-kV connection is standard; sanctioned demand sits between 200 and 500 kVA.

Recommended sizing: 200–400 kWp depending on roof availability and night-load share. The lower end (200 kWp) suits hospitals where solar will only target the highest-tariff daytime hours; the upper end (400 kWp) covers near-full daytime load with some afternoon export. Roof area required: 15,000–30,000 sqft. Most 100-bed facilities exhaust available roof area at 250–300 kWp and either stop there or push the rest onto adjacent ground-mount or canopy structures.

All-in CAPEX: ₹70 lakh to ₹1.4 crore (₹35 per Wp turnkey). A 400 kWp system generates ~6,00,000 kWh/year, saving ₹14 lakh annually at ₹8.50/kWh against the HT tariff. With AD claimed (40% × 80% × 30% on ₹1.4 cr = ₹13.4 lakh Year-1 shield), effective CAPEX falls to ~₹1.27 crore. Payback: 5 years.

For the full 100-bed financial model — including night-load coverage, lithium battery vs lead-acid sizing, DG (Diesel Generator) hours displaced, and ICU back-up architecture — read our solar for private hospital 100-bed deep dive.

The roof-vs-ground tradeoff at 100-bed. Hospitals that exhaust roof area at 250 kWp face a real choice: stop there or push to ground-mount on adjacent land (where available) and parking canopies. Parking canopies cost ₹42–48/Wp turnkey (vs ₹35/Wp on flat roof) — a 33% premium — but they deliver dual value: solar generation plus shaded parking, which patients and staff visibly appreciate. Boards that prioritise patient-facing optics often choose canopies even where rooftop alone would suffice. For hospitals where land or canopy area is unavailable, the answer is to stop at the roof-limited capacity and consider Group Captive open-access for the remaining demand — see the financing section below.

Free 30-minute hospital solar audit. Send us your last 12 months of HT bills and a roof drawing — we’ll come back with a sized proposal, AD impact model, and OPEX-vs-CAPEX comparison within five working days. Talk to the Heaven Green commercial team →

250-Bed Hospital — 500 kWp to 1 MWp Solar Math

Tertiary-care hospitals at the 250-bed scale are the inflection point where solar moves from “nice operating saving” to a board-level capex line item. Daily load: 3,000–6,250 kWh (90,000–1,87,500 kWh/month). Annual electricity bill: ₹1.0–1.7 crore. These facilities typically run six to ten OTs, 30–50 ICU beds, central sterilisation, full imaging (MRI + CT + cath lab + nuclear medicine in some), and a 600–1,500 kVA HT connection.

Recommended sizing: 500 kWp to 1 MWp. The driver is roof area more than electrical sizing — a 250-bed hospital almost always has roof area between 30,000 and 60,000 sqft across the main block, IPD block, and parking canopies. Solar carport structures over staff and patient parking add 100–200 kWp of usable area without consuming clinical roof real estate.

All-in CAPEX: ₹1.75 crore (500 kWp) to ₹4 crore (1 MWp) at ₹35 per Wp; large 1 MWp projects sometimes drop to ₹3.5 crore on competitive bids. A 1 MWp system generates 15,00,000 kWh/year, saving ₹35–40 lakh annually at ₹9/kWh. With AD: Year-1 tax shield ≈ ₹40 lakh on a ₹4 cr CAPEX (40% × 80% × 30%). Effective CAPEX ~₹3.6 crore, payback 4.5–5 years.

This bracket also makes economic sense for Group Captive structures — where the hospital takes 26% equity in a special-purpose solar generation company and consumes power from it under the Electricity Rules 2005 Open Access framework. Group captive saves the cross-subsidy surcharge (~₹1.20/kWh in most states) and additional surcharge, taking the effective landed cost of solar to ₹3.50–4.20/kWh.

Net-metering vs net-billing at 250-bed scale. Most state DISCOMs cap residential net-metering at 1 MWp under HT commercial connections, and several push large hospitals onto net-billing — where exported units are paid at the Average Power Purchase Cost (APPC) of ₹2.50–3.50/kWh rather than the retail HT tariff. This is why 250-bed solar systems should be sized to self-consume 90–95% of generation rather than exporting heavy surplus. The sizing engineering for this bracket therefore hinges on the night-load share: hospitals with a 40%+ night-load share (24×7 ICUs, full DG-run sterilisation cycles) can deploy 1 MWp confidently; hospitals with a quieter night curve should cap at 700–800 kWp to keep self-consumption above 90%.

500-Bed Hospital — 1 to 2 MWp Solar Math

Super-speciality 500-bed hospitals — the Apollo / Fortis / Max / Manipal class of facility — have daily loads of 6,000–12,500 kWh, monthly consumption of 1.8–3.75 lakh kWh, and annual electricity spend frequently above ₹3 crore. HT connection: 1,500–3,000 kVA. The clinical mix typically adds organ transplant units, oncology with linear accelerators, neonatal ICUs, and 24×7 cath labs — pushing energy intensity to the upper end of the 12–25 kWh/bed/day band.

Recommended sizing: 1 to 2 MWp. Available roof and ground area is the binding constraint. A 500-bed campus typically has 60,000–1,00,000 sqft of total available area across the main hospital roof, adjacent OPD building, MEP (Mechanical Electrical Plumbing) plant rooms, parking canopies, and any vacant adjacent land. A 2 MWp system needs 1.0–1.4 acres equivalent — feasible on campuses with attached land but not on dense urban sites.

All-in CAPEX: ₹3.5 crore (1 MWp) to ₹7–7.5 crore (2 MWp). A 2 MWp system generates 30,00,000 kWh/year, saving ₹70–80 lakh annually. AD Year-1 tax shield on ₹7.5 cr CAPEX: ~₹72 lakh. Effective CAPEX: ~₹6.78 crore. Payback: 4–5 years.

At this scale, large hospital chains (Apollo, Fortis, Manipal, Narayana) increasingly run Group Captive structures across multiple sister hospitals — a 5–10 MWp solar park feeding 4–6 hospital sites through open access. The economics improve further: landed tariff of ₹3.20–3.80/kWh, vs CAPEX-rooftop levelised cost of ₹4.50–5/kWh and grid tariff of ₹8–10/kWh.

Hybrid 500-bed deployments. Practically, very few 500-bed campuses do a single 2 MWp rooftop in one go — the typical pattern is a CAPEX-owned 800 kWp to 1 MWp rooftop slice (to claim AD on the asset side) plus a Group Captive open-access contract for the remaining 3–5 MWp of underlying load. This hybrid structure captures both the tax shield on the owned slice and the structurally cheaper open-access tariff on the bulk. The accreditation and audit logic also favours this split — the rooftop slice physically demonstrates the hospital’s sustainability commitment for NABH and IGBC reviews, while the open-access contract delivers the bulk of the financial benefit. Heaven Green has scoped this hybrid pattern across multiple tertiary campuses; the underlying engineering is straightforward but the contracting and DISCOM coordination takes 4–6 months end-to-end.

Financing Options — CAPEX, OPEX, Group Captive

Hospitals have three primary financing structures for solar in 2026. The right choice depends on cash position, tax bracket, balance-sheet appetite, and time horizon.

Model	Upfront cost	Effective tariff / saving	Best for	Constraint
CAPEX (own)	100% (₹35–40/Wp)	₹4.50–5/kWh levelised; full AD benefit	High-tax-bracket hospitals with surplus cash	Lock-in of ~₹4 cr per MWp; balance-sheet impact
OPEX / PPA	Zero	₹4.50–5/kWh, 15–25 year PPA	Cash-conscious hospitals; new builds	Land/roof licence to developer; no AD benefit
Group Captive (26% equity)	~26% of project value	₹3.20–4.20/kWh delivered	Multi-hospital chains; 1 MWp+ scale	Special-purpose company structure required
Hybrid (part-CAPEX, part-OPEX)	30–50%	Blended ₹4–4.80/kWh	Hospitals wanting AD on a core 200–300 kWp slice and OPEX for the balance	Slightly more complex structuring

A complete CAPEX-vs-OPEX comparison for hospitals — including the EBITDA-vs-cash-flow optics that hospital CFOs use to choose between the two — sits in our OPEX vs CAPEX for hospital solar guide. For the wider sector-agnostic decision matrix, see OPEX vs CAPEX — which is better in 2026. And for the specific AD calculations including the Year-1 vs Year-2 split, written-down value, and MAT (Minimum Alternate Tax) interaction, read Accelerated Depreciation in solar — the tax playbook.

Quick CFO heuristic. If the hospital’s 30% corporate tax outgo on annual profit is greater than 25% of the proposed solar CAPEX, CAPEX-with-AD is the right call — the tax shield monetises quickly. If the hospital is in a tax holiday under §10AA, MAT-only regime, or carrying forward losses from a recent expansion, OPEX/PPA dominates because AD is wasted. For multi-site chains running 5+ MWp aggregate consumption, Group Captive is the default — the structural cost advantage of saving cross-subsidy surcharge is too large to ignore. The cleanest path for hospital boards undecided between the three is a side-by-side 10-year cash-flow model showing CAPEX outflow, AD inflow, OPEX-PPA tariff escalation, and Group Captive equity outflow — Heaven Green publishes this model as part of every proposal.

Common Hospital Solar Sizing Mistakes

Across the hospital solar projects Heaven Green has scoped between 2022 and 2025, the sizing mistakes that derail payback or fail NABH inspection cluster around six repeat patterns. All preventable with a proper Day-0 load study.

1. 1
   Sizing against connected load instead of measured kWh. A 100-bed hospital with 500 kVA sanctioned demand rarely consumes more than 250 kW peak. Sizing solar against 500 kVA over-builds by 80% and tanks payback. Always size against last 12 months of HT bills.
2. 2
   Ignoring NABH UPS-DG synchronisation requirements. Solar must not interfere with the ICU/OT UPS (Uninterruptible Power Supply) failover chain. Skipping this design check causes commissioning delays of 3–6 weeks while protection relays are reconfigured.
3. 3
   Over-counting roof area without shading study. Water tanks, AHU (Air Handling Unit) housings, helipads, oxygen vent stacks, and parapets reduce usable roof area by 20–35%. Skipping a shading analysis is the most common cause of 12–18% generation underperformance.
4. 4
   Choosing non-ALMM modules to chase a lower per-Wp quote. DCR (Domestic Content Requirement) and ALMM compliance are not optional for any commercial system claiming AD; the resulting tax disallowance dwarfs the per-Wp saving.
5. 5
   Skipping fire-rated cabling and BIS earthing on rooftop runs. Hospital rooftops are NABH-audited; non-compliant DC cabling (IS 14255) and earthing (IS 3043) trigger accreditation findings that take months to close out.
6. 6
   Locking into an OPEX PPA without escalation cap. A flat-tariff PPA looks great in Year 1 but if grid tariff drops faster than the PPA escalation, the hospital loses. Cap the PPA escalation at the lower of 3% or CPI.

CAPEX vs OPEX vs PPA for Hospital

The three-way decision between owning the asset (CAPEX), licensing the roof to a third-party developer (OPEX/PPA), and joining a Group Captive structure is the single biggest financial call any hospital board makes on solar. The right answer changes with tax position, cash position, balance-sheet appetite, and accreditation cycle. Here is the head-to-head.

Verdict. For a 50-bed or 100-bed hospital in the 30% corporate tax bracket with surplus cash, CAPEX with full AD claim wins — 5-year payback and a 22–28% IRR is hard to beat. For 250-bed and 500-bed facilities in growth-capex mode (where every crore is earmarked for diagnostic or surgical equipment), OPEX / PPA wins — zero upfront, immediate ₹35–80 lakh/year saving, no balance-sheet hit. Hospital chains spanning 3+ sites should look hard at Group Captive — landed tariff of ₹3.20–4.20/kWh is structurally cheapest at scale.

How Heaven Green Energy Designs Hospital Solar

Heaven Green Energy is an MNRE-aligned solar EPC (Engineering, Procurement, Construction) contractor with hospital installations across the 50-bed to 500-bed range, including nursing homes in tier-3 cities, multi-speciality facilities in Jaipur, and tertiary-care campuses on PPA structures. Every hospital project we design runs through a NABH-aligned design checklist that gates the engineering before tendering.

Checklist item	Standard / authority	Stage
12-month load study against HT bills	Heaven Green load-curve model	Day 0
Roof / ground area shading study (PVsyst)	IGBC Green Healthcare 2024	Day 0–7
NABH UPS-DG synchronisation design	NABH 5th ed. — facility & engineering	Day 7–14
ALMM-listed tier-1 module selection	MNRE ALMM list	Tender
BIS / IS-compliant cabling & earthing	IS 14255 (cables), IS 3043 (earthing)	Tender
Single-line diagram + DISCOM net metering filing	State DISCOM, MNRE Net Metering Regulations	Day 14–30
Fire-rated DC cable trays, lightning protection	IS 2309	Engineering
Battery sizing for critical-load back-up (where required)	NMM (Hospital Master Plan) standards	Engineering
AMC (Annual Maintenance Contract) — 5+5 year option	Heaven Green O&M template	Post-commissioning
Performance-linked retention (5% of EPC value)	Heaven Green commercial terms	Contracting

The services that match common hospital project scopes:

• Commercial Solar — 50 kWp to 1 MWp rooftop hospital systems with ROI modelling and AD planning.
• Industrial Solar — 1 MWp+ ground-mount and rooftop systems for tertiary-care campuses and hospital chains.
• Solar EPC Services — turnkey delivery with performance guarantees and NABH-aligned engineering.
• Get a hospital solar audit — send your last 12 months of HT bills and a roof plan; we’ll return a sized proposal in 5 working days.

For complementary deep-dives on the financing and tax topics that recur in every hospital board discussion, see OPEX vs CAPEX for hospital solar, the wider OPEX-vs-CAPEX decision matrix, the Accelerated Depreciation tax playbook, and the lithium vs lead-acid battery sizing guide for hospitals adding critical-load back-up.

Frequently Asked Questions

How much does solar cost for a 50-bed hospital in 2026?

A 100 kWp turnkey rooftop system for a 50-bed hospital costs ₹35–40 lakh all-in (₹35–40 per Wp) including ALMM-listed tier-1 modules, BIS-certified inverters, mounting structure, AC/DC cabling, switchgear, NABH-aligned UPS-DG synchronisation, monitoring, and commissioning. Generation: ~1,50,000 kWh/year; annual savings: ₹12.75 lakh gross or ₹3.5–4 lakh net depending on day-time self-consumption share. Payback with AD claimed: 5–6 years.

What size solar system does a 100-bed hospital need?

A 100-bed multi-speciality hospital typically needs 200–400 kWp depending on daytime load share and roof availability. The lower end (200 kWp) suits hospitals targeting only high-tariff daytime hours; the upper end (400 kWp) covers full daytime load and exports some surplus. Roof requirement: 15,000–30,000 sqft. Indicative CAPEX: ₹70 lakh to ₹1.4 crore. Annual savings at full size: ~₹14 lakh. Payback with AD: ~5 years.

What is the payback period for a 250-bed hospital solar installation?

A 250-bed tertiary care hospital installing a 1 MWp solar system at ₹3.5–4 crore turnkey saves ₹35–40 lakh annually at HT tariffs of ₹9/kWh. With Accelerated Depreciation claimed at 40% on 80% of CAPEX in Year 1 (~₹40 lakh tax shield at 30% corporate tax), effective CAPEX falls to ~₹3.6 crore. Payback lands at 4.5–5 years. Group Captive structures pull this further to under 4 years.

How does AD (Accelerated Depreciation) work for hospital solar?

Under Section 32 of the Income Tax Act, hospitals can claim 40% Accelerated Depreciation on 80% of solar CAPEX in Year 1, plus another 40% on the written-down value in Year 2. At a 30% corporate tax rate, this delivers a Year-1 tax shield of roughly ₹9.6 lakh per ₹1 crore of CAPEX — effectively reducing the upfront cost by 9–11% in Year 1 and another 6–7% in Year 2. AD only applies to CAPEX (owned) systems, not to OPEX/PPA arrangements.

Is OPEX or CAPEX better for a hospital installing solar?

CAPEX wins for hospitals in the 30% corporate tax bracket with surplus cash and a 5+ year horizon — full AD benefit plus 25-year levelised cost of ₹4.50–5/kWh delivers IRR of 22–28%. OPEX/PPA wins for hospitals in growth-capex mode, tax holiday, or with balance-sheet constraints — zero upfront, ₹4.50–5/kWh tariff vs ₹8–10/kWh grid means immediate ~45% energy-cost saving with no capital lock-up. Group Captive wins for hospital chains spanning 3+ sites at 1 MWp+ total scale.

Can solar run a hospital’s critical loads — ICU, OT, MRI — directly?

Solar alone cannot run hospital critical loads directly because rooftop PV is variable and does not provide UPS-grade voltage stability. The standard NABH-compliant architecture is: solar offsets the general HT consumption during daytime, while ICU/OT/MRI critical loads continue to draw from the UPS-DG-grid chain unchanged. A battery storage layer can be added for evening / outage back-up of critical loads, but the solar PV array itself does not directly feed clinical equipment without a UPS in between.

How much roof area does a 500-bed hospital need for 2 MWp of solar?

A 2 MWp solar system requires approximately 60,000–1,00,000 sqft of unshaded roof or equivalent ground / canopy area — roughly 1.0–1.4 acres equivalent. Most 500-bed super-speciality campuses meet this through a combination of main hospital roof, OPD building roof, MEP plant rooms, parking canopies, and any adjacent vacant land. Dense urban campuses may need to combine on-site rooftop with off-site Group Captive open-access to hit the full 2 MWp.

Does solar affect a hospital’s NABH accreditation?

Solar can support NABH accreditation when designed correctly — IGBC Green Healthcare rating credits, reduced grid dependency, and lower carbon footprint all align with NABH’s 5th-edition facility and environment standards. The critical design constraint is that solar must not interfere with the UPS-DG synchronisation chain that feeds OT and ICU loads. Non-compliant DC cabling (must meet IS 14255), earthing (IS 3043), and fire-rating (IS 2309 for lightning protection) trigger NABH findings and must be designed in from Day 0, not retro-fitted.

What is Group Captive solar and which hospitals should consider it?

Group Captive is an open-access framework under the Electricity Rules 2005 where the power consumer (hospital) takes 26% equity in a special-purpose generation company and consumes power from it. The hospital saves cross-subsidy surcharge (~₹1.20/kWh) and additional surcharge, taking the effective landed cost to ₹3.20–4.20/kWh — structurally cheaper than CAPEX rooftop (₹4.50–5/kWh) and far below grid (₹8–10/kWh). Best suited to multi-site hospital chains (Apollo, Fortis, Manipal, Max) running 5 MWp+ aggregate consumption, where a single 5–10 MWp solar park can feed 4–6 sister hospitals through open access.