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Pilot ProjectNet Energy PositiveIGBC PlatinumPune

Scorpio - Fortune Estates

India's First Net Energy Positive Affordable Housing Project

IGBC Green Homes – Platinum

Pune, Maharashtra

24

Apartments

41.28 kWp

Solar Installed

66,000 kWh

Generated / Year

IGBC Platinum Rated Building

Green Rating

The Problem

Green buildings that weren't green for the people living in them.

Residential buildings in India faced a fundamental barrier: rooftop solar could only power common areas, leaving every individual apartment entirely dependent on the grid. Residents of green-certified buildings continued to pay full electricity bills, and there was no technology to equitably meter and distribute solar energy to each homeowner in a multi-unit building — rendering green certification meaningless at the household level.

42%

of global CO₂ from real estate

10M+

affordable homes needed in India by 2030

70%

of India's 2030 building stock is yet to be built

The Building

Scorpio, Fortune Estates — at a glance

Site Area

1,204 sq m

Built-up Area

2,651 sq m

Floors

Stilt + 6 floors

Unit Type

2-BHK · 900 sq ft

Completed

2019

Total Units

24

Developer

Oricon Developers

Technology

Protostar Technologies

On Risk & Conviction

Oricon bore the full construction cost without any presales. Because Scorpio's features were entirely experimental — never tested at scale before — RERA required waiting for the Completion Certificate before a single unit could be sold. Both father and son proceeded on conviction alone.

The Solar Story

Solar for every apartment — not just the lobby.

The Rooftop System

A 41.28 kWp solar PV array covers the entire rooftop, generating 66,000 kWh of clean energy annually — enough to power every common area and deliver 100 free units per apartment per month.

Raised on a framework, not flat-mounted.

Most builders mount panels directly on the terrace floor. The panels at Scorpio were raised on a framework — creating usable communal terrace space for residents, protecting the waterproofing membrane from direct sun exposure, and allowing airflow beneath the panels to improve panel performance.

Grid-connected with net metering carry-forward.

Maharashtra's regulations allow surplus solar to be carried forward within the same year. Excess generated during peak summer months accumulates as credit — drawn down during the monsoon when cloud cover reduces generation to 40–50% of rated capacity.

The SPDU — The Invention That Made It Possible

Smart Power Distribution Unit · Patented

No smart meter available anywhere in India could simultaneously give individual apartments their allocated share of solar energy while keeping them seamlessly connected to the grid as a fallback. Rahul went back to the drawing board: designed the SPDU from first principles, built a prototype, and tested it in his own home. After debugging every edge case, he filed a patent. A manufacturing partnership was established to produce the units at scale, which were then installed in the ground-floor meter room serving all 24 flats. Each apartment gets 100 free solar units per month — and when the quota is consumed, the system switches to grid power silently, with no interruption. Some residents ended up drawing only 10–15 additional grid units a month.

100

free units/month

per apartment from solar

10–15

grid units

some residents' total monthly top-up

24

apartments

individually metered and managed

Hot Water: Done Right

Three hot water technologies existed. Only one worked year-round, efficiently, and without ongoing grid dependency.

Electric Geyser

High operating cost every month. COP 0.95 — nearly all energy is wasted as heat. High carbon footprint.

EfficiencyCOP 0.95
SeasonalNo
24/7 supplyYes

Solar Water Heater

Worst when demand is highest. Cloud cover in monsoon and winter cuts output dramatically — forcing residents back to electric geysers.

Efficiency~70%
SeasonalYes
24/7 supplyNo

Heat Pump

EfficiencyCOP 6.0 at Scorpio
SeasonalNo
24/7 supplyYes

The Engineering Insight

The cold exhaust from the heat pump was rerouted into the stairwell and floor landings — passively cooling the entire building's interior.

A standard heat pump runs at COP 3.5. By connecting it to rooftop solar and rerouting its cooling byproduct through the building, Scorpio achieved an effective COP of 6.0 — every 1 unit of electricity consumed produces 3.5 units of heat and 2.5 units of cooling simultaneously. The 3,500L tank meets the building's entire 2,880L daily hot water demand, around the clock.

1 unit in → 6 units of work out

Beyond Solar

The full engineering picture

Solar was the headline. These are the decisions that made Scorpio genuinely net positive — across energy, water, and materials.

Passive Design

96% of roof area reflective-coated

Double walls on the east and west faces block afternoon heat gain before it enters the building. 96% of roof area is coated with reflective materials; 100% of non-roof area uses high-SRI surfaces to counter the urban heat island effect. 15% of the site was reserved as green space, with natural topography and soil permeability fully retained.

EV Charging — Since 2016

Every parking lot pre-wired

In 2016–17, when EVs were still a fringe concept in India, 15-ampere sockets were pre-wired at every single parking lot — with clean concealed installation and no exposed conduits. Rahul was driving a Mahindra e2o at the time. Residents are now buying EVs because the infrastructure was already there when they needed it.

Energy Recovery

80–90% reduction in common area lighting consumption

Motion sensors on every common area light cut consumption by 80–90%. The elevator is fitted with a regenerative dynamo that converts the kinetic energy of a descending cab back into usable electricity — feeding it directly into the building's electrical infrastructure.

Water: Every Drop Accounted For

37.4% water use reduction

A dual-sedimentation rainwater harvesting system recharges the groundwater table via borewell injection — on a compacted permeable base, not a sealed concrete bed. Ultra-low-flush WCs use 4L/2L vs. the 8L/6L industry standard at the time, using Jaguar flush valves rarely specified by Indian developers. All taps and showers have built-in low-flow aerators.

Construction Circularity

96% of construction waste diverted from landfill

12,809 of 13,328 kg of construction waste was reused, recycled, or diverted from landfills. 52% of materials by cost were sourced within 400 km of the site. 20% by cost had recycled content. 100% of wood was rapidly renewable and Kit-ply certified — sourced from Poplar, Bamboo, and Eucalyptus.

Waste Operations

50 kg/day composting capacity on-site

An Organic Waste Composter handles 50 kg of bio-degradable waste daily; the compost is reused as landscaping manure. Each unit has segregated bins for dry and wet waste. A shared common facility manages e-waste, batteries, and lamps separately — keeping all streams out of general landfill.

Outcomes

What Scorpio actually delivered

100 free units/month

Solar per Apartment

111.63 t/year

CO₂ Offset

37.4%

Water Use Reduction

IGBC Platinum Rated Building

Green Rating

Net Positive

Net Energy Status

96%

Construction Waste Diverted

₹0

Green Premium Charged

Life at Scorpio

From the people who live there

Living in Scorpio has been a step up for my family because we have experienced a lifestyle upgrade without even trying. Having 24x7 hot water feels like a luxury I didn't know I needed, and being able to enjoy guilt-free air conditioning during the summer months is a relief, especially this year.

Swapnil

Resident, Scorpio – Fortune Estates

Having solar in my flat has significantly slashed my bills. While neighbors from my previous building face soaring electricity costs, I've remained in the lowest tariff slab thanks to the 100 units from solar. Plus, the EV charging in our parking has inspired my son to plan for an electric vehicle.

Yogita

Resident, Scorpio – Fortune Estates

Once homebuyers understand the lifecycle savings from green building features, their concern about paying a premium will change entirely. Scorpio proved it's possible to make solar energy truly individual — and truly free.

Rahul Rajan

Partner - Oricon Developers, Founder - Protostar Technologies Pvt. Ltd.

Recognition

Independently validated at every level

IGBC Platinum Rating

Indian Green Building Council — Hadapsar's first residential project · 2019

Bharat Leadership Award — Green Entrepreneurship in Real Estate

Awarded by the Governor of Maharashtra · 2021

National Commendation Certificate — Performance Challenge for Green Built Environment

Indian Green Building Council · 2021

AESA Award — Special Jury Recommendation, Green Initiatives

Architects Engineers & Surveyors Association · 2020

Times Real Estate Icons — Top Environmental Friendly Project, West India

Times Group · 2020

WIDE Angle Forum Award — Best Standalone Multi-tenement Building

WIDE Angle Forum · 2022

SUNREF India Programme — Selected among India's top 11 green affordable housing projects

Agence Française de Développement · European Union · National Housing Bank · 2022

Academic & Research Publications

What Came Next

From one building to every building

Scorpio took 30 months to build. But there are hundreds of thousands of residential buildings across India with bare rooftops — their residents paying full electricity bills, their waterproofing degrading under unshielded sun. The SPDU, invented to solve Scorpio's solar distribution problem, can retrofit any existing building in approximately 3 months. No reconstruction. No disruption. That possibility became Protostar Technologies.

For Developers

Build the next Scorpio.

We've already solved the hardest problems — solar distribution, individual metering, heat pump integration, EV infrastructure. Integrate SPDU into your next project from day one.

Talk to us

For Existing Buildings

Retrofit, not rebuild.

Your building already has a rooftop. The SPDU can retrofit solar distribution to every individual apartment in approximately 3 months — no reconstruction, no disruption to residents.

See the technology

Ready to deploy solar to every apartment?

Whether you're designing a new building or managing an existing one, the SPDU is ready.