Lower cut-in speed
Modern rotor geometries and low-friction generators begin producing in a light breeze rather than needing a sustained gale, which is what made older machines useless in urban air.
New technology · now quotable
Wind turbines small enough for a rooftop, serious enough to matter
A new class of compact turbines generates through the night and the monsoon — the two windows where a solar-only building falls back on the grid. SunX assesses, installs and maintains them for homes, campuses and industry.
Why add wind
Solar stops at sunset. Your building does not.
A rooftop PV array produces on a bell curve peaking at midday and reaching zero by evening. Most homes and many industries consume the opposite way — heaviest in the evening, through the night, and all through a cloudy monsoon week.
That mismatch is why a solar-only building still imports a large share of its units, and why storage alone gets expensive: batteries have to be sized for every hour the sun is absent. A small wind turbine attacks the problem from the other side. Wind in the Deccan typically strengthens in the late afternoon and evening and holds up through the south-west monsoon, exactly when irradiation collapses.
Put PV and a turbine on the same hybrid inverter and the combined generation curve flattens out. The battery you need gets smaller, the share of self-consumed units goes up, and the grid becomes a back-up rather than a supplier.
- Complementary, not competing — wind and solar peak at different hours and in different seasons.
- Small footprint — a turbine occupies a mast base or a few square metres of terrace, leaving your roof free for panels.
- Generates in weather that kills PV output — overcast, rain and storm fronts are wind events.
- Smaller battery for the same independence — because the gaps you are covering are shorter.
Evening peak
Wind speeds across the Telangana plateau commonly rise after 3 pm and hold into the night.
Monsoon cover
June to September costs a PV array a large share of its yield. It is a strong wind season.
What changed
Why small wind is worth a second look
If you looked at rooftop wind a decade ago and walked away, you were probably right to. Four things have changed since.
Noise and vibration solved
Vertical-axis designs and damped mounting brought sound and structural vibration down to levels that are acceptable on an occupied building — historically the deal-breaker.
Hybrid inverters matured
One inverter now manages PV, wind, battery and grid together with proper MPPT on each source. Earlier you needed parallel systems that fought each other.
Cost per kW fell
Volume manufacturing has brought small-turbine pricing into a range where, on a genuinely windy site, the units it produces compete with what the DISCOM charges.
We will also tell you when it does not fit. Small wind is site-sensitive in a way solar is not. A turbine in turbulent air behind taller buildings, or on a structure that cannot take the load, is a bad investment — and we would rather lose the order than install one.
What we install
Three configurations, chosen by your site
The right machine depends on how clean your airflow is, how much height you can get and what the structure can carry.
Vertical axis
Rooftop vertical-axis turbines
Compact VAWTs for terraces and shed roofs in built-up areas. They accept wind from any direction and cope far better with the swirling, gusty air you get between buildings.
- Typical range 1 kW to 10 kW per unit
- Omnidirectional — no yaw mechanism to fail
- Low profile, low noise, damped mounting
- Installed singly or as a row along a parapet
Hybrid
Wind-solar hybrid with storage
Our most recommended configuration. PV carries the day, the turbine carries the evening and the monsoon, and an LFP battery bridges what neither covers. One inverter, one app, one contract.
- Flatter generation curve, higher self-consumption
- Smaller battery for the same independence
- Genuine off-grid capability where the grid is weak
- Single monitoring platform for all sources
Horizontal axis
Mast-mounted turbines for industry & farms
Where you have open land and can get real height, a conventional three-blade machine on a guyed or free-standing mast produces significantly more per kW than any rooftop unit.
- Typical range 5 kW to 50 kW per machine
- Mast heights selected from the wind profile
- Foundation design and structural certification
- Suits factories, farms, cold stores, resorts
How we qualify a site
No turbine is quoted before the site earns it
Solar can be estimated from a satellite image and a bill. Wind cannot. This is the sequence we follow before we will put a number on paper.
Wind resource review
We start from published wind-atlas data for your location and elevation, then adjust for terrain, surrounding building height and the exposure of your specific roof or plot.
On-site measurement
Where the desk study is promising but not conclusive, we install an anemometer at the proposed hub height and log real wind speed and direction before committing to a machine.
Structural & vibration check
Dead load, thrust load and dynamic behaviour assessed against your slab, parapet or purlin structure — with a mast and foundation design where the roof is not the right host.
Yield model & decision
An annual energy estimate for the specific turbine, with the payback shown against wind alone and against a hybrid with PV. If it does not clear, we say so and quote solar only.
What makes a good wind site
- Open exposure on the prevailing wind side — ideally west to south-west here
- Nothing significantly taller within roughly ten times its own height upwind
- A structure that can carry both static and dynamic load, or room for a mast
- Load that continues after dark — so the units generated are consumed, not just exported
What makes a poor one
- A low roof hemmed in by taller neighbours — turbulent air, little energy
- Lightweight or ageing roof structures where vibration is a real risk
- Sites with a purely daytime load and generous net metering — solar alone wins
- Locations where local rules restrict roof-mounted moving equipment
Solar vs wind vs hybrid
How the three options actually differ
A plain comparison, so you can see why we recommend what we recommend.
| Rooftop solar | Small wind | Wind-solar hybrid + storage | |
|---|---|---|---|
| Generates | Daylight hours, peaking midday | Whenever wind blows — often evening and night | Around the clock, with storage covering the gaps |
| Best season | October to May | May to September (monsoon and pre-monsoon) | All year, by design |
| Site sensitivity | Low — needs a shade-free roof | High — needs clean, exposed airflow | Moderate — PV carries sites where wind is marginal |
| Space needed | About 80 sq ft per kW | A mast base or a few square metres | Roof for PV, plus a turbine position |
| Maintenance | Cleaning and annual electrical checks | Cleaning, plus periodic bearing and fastener inspection | Both, on one schedule |
| Central subsidy | Yes, for eligible homes under PM Surya Ghar | Not covered by the residential rooftop scheme | On the PV portion only |
| Typical payback | Shortest of the three | Longer, and highly site-dependent | Between the two, with the best energy independence |
| We recommend it when | You have a good roof and a daytime load — almost always start here | You have genuinely windy, exposed land and evening load | Outages are costly, or you want to run largely off your own generation |
Subsidy and scheme eligibility change from time to time. We confirm what applies to your project at the time of proposal.
Wind FAQs
What people ask us about rooftop wind
Modern vertical-axis machines mounted on damped brackets are quiet enough for occupied buildings — most of what you hear at close range is airflow rather than mechanical noise. It is not silent, though, and we assess where the nearest bedroom or office is before choosing a position. Where noise or vibration cannot be managed acceptably, we will say so.
That is exactly what the structural check answers. A turbine applies a static dead load plus a dynamic thrust load that varies with wind speed, so it has to be transferred into the building properly — usually onto a beam, column line or a dedicated base frame rather than mid-span slab. Where the roof is not suitable, a ground or side-mounted mast is often the better answer.
Honestly: it depends far more on your site than on the machine. Output rises with the cube of wind speed, so a modest difference in average wind at hub height changes the answer dramatically. That is why we do a resource study — and, on borderline sites, real measurement — instead of quoting a brochure figure. Anyone giving you a generation number for a rooftop turbine without looking at your site is guessing.
The PM Surya Ghar residential subsidy applies to solar PV, not to small wind. Businesses can usually claim depreciation benefits on the asset, and state or MNRE programmes for small wind and hybrid systems change periodically — we check what is live when we prepare your proposal. In a hybrid system the PV portion remains eligible on its own merits.
More than a solar panel, less than a generator. It has moving parts, so the schedule covers fastener torque, bearing condition, blade inspection for damage or imbalance, and the electrical side including the controller and braking system. We cover all of it under an annual contract, and monitoring flags a drop in output between visits.
Find out if your site qualifies
Ask for a wind assessment — we will give you a straight answer
Send us your location and a photograph of the roof or plot. We will come back with a first-pass view on whether a turbine is worth pursuing, and what a hybrid would look like alongside solar.