Hybrid solar calculator

Pick the appliances that have to keep running during a power cut and how long cuts last. You get the inverter, the UTL batteries, the panels, the roof area and a price after the subsidy. No phone number needed.

Battery type

What has to run on the battery?

Only what you need during a cut. Most homes back up lights, fans, the fridge and Wi-Fi, and leave ACs and geysers on the grid.

LED bulbs (9 W)

LED tube lights (20 W)

Ceiling fans, regular

Ceiling fans, BLDC

Refrigerator

TV

Wi-Fi router

Laptop

Desktop computer

CCTV system (4 cameras)

Air cooler

1 ton inverter AC

1.5 ton inverter AC

Water pump, 1 HP

Washing machine

Iron

Mixer grinder

Microwave

How it sizes a hybrid system

  1. The inverter has to carry everything on backup at once, plus a motor starting. A fridge compressor or a pump draws two to three times its running power for a few seconds, and an inverter can briefly carry about 2 times its rating.
  2. The battery covers the appliances you chose for the length of one cut. Pumps, irons and mixers only count for the few minutes they actually run.
  3. Batteries are sized so they aren’t drained too far: about 80% for lithium and 50% for tubular, after 10% inverter losses. The battery voltage follows the inverter, as in UTL’s kits: 24 V at 1 kVA, 48 V at 2 to 3 kVA, 96 V at 5 kVA.
  4. Panels have to refill the battery on a sunny day. The standard kit is never smaller than the inverter, and each kW of panels needs about 100 sq ft of roof.
  5. The price is our standard hybrid kit of that size, less the PM Surya Ghar subsidy, because hybrid systems stay connected to PSPCL.

For the bill saving on your PSPCL connection, the bill calculator sizes hybrid systems from your bill. Hybrid solar systems covers how they work and what they cost. No grid at all? Use the off-grid calculator.

Typical hybrid systems

From the calculator. Prices are for our standard hybrid kit of each size; the battery bank shown can change them.

CaseInverterBatterySystemRoofAfter subsidy
Lights, fans, fridge, TV and Wi-Fi, 4-hour cut, lithium 1 kVA 2 × lithium 1 kW 100 sq ft ₹1,75,000 to 1,95,000
The same with tubular batteries 1 kVA 2 × tubular 1 kW 100 sq ft ₹1,75,000 to 1,95,000
The same for an 8-hour cut 1 kVA 3 × lithium 2 kW 200 sq ft ₹1,82,000 to 2,06,000
The same plus a 1.5 ton AC 3 kVA 2 × lithium 3 kW 300 sq ft ₹2,00,000 to 2,28,000

The first case in full, as the calculator shows it.

Worked example: backup for a 4-hour power cut

Suggested system

1 kW hybrid

Runs the appliances you chose for about 4 hours of a power cut, and cuts your bill the rest of the time.

Needs about 100 sq ft of shade-free roof, at 100 sq ft per kW.

What goes into it

Inverter599 W running together, plus starting surge1 kVA
Battery bankUTL 25.6 V, 100 Ah lithium, 5.1 kWh at 24 V2 × lithium
Solar panelsat least 1 kW to refill the battery on a sunny day1 kW
Roof areaabout 100 sq ft
Units from the battery in one cut1.9 units

Price

Estimated price range. Prices are indicative and subject to change. Contact us for the latest pricing and a customised quotation.

1 kW hybrid system, installedOur standard hybrid kit of this size, which comes with one 51.2 V, 100 Ah lithium battery. The battery bank above can change the price, and we confirm it when we quote.₹2,05,000 to 2,25,000
PM Surya Ghar subsidy, homespaid to your bank after PSPCL inspects the system− ₹30,000
After subsidy₹1,75,000 to 1,95,000
Units by appliance
ApplianceUnits in one cut
3 × Ceiling fans, regular0.9
1 × Refrigerator0.3
1 × TV0.3
6 × LED bulbs (9 W)0.2
2 × LED tube lights (20 W)0.2
1 × Wi-Fi router0.0

Turn this into a quote

Send us the estimate and your address. We check the roof, the wiring and which circuits to back up, and come back with a system and a price.

This is an estimate for a first conversation. The inverter is sized to what runs together plus a motor starting, the battery to be used to about 80% (lithium) or 50% (tubular) each cycle, and the panels to 3.4 units per kW a day. We fix the design after a site survey, and we don’t promise a particular backup time, bill or saving.

Questions we are asked

How many batteries do I need for a hybrid solar system?

It depends on what has to run during a cut and for how long, not on the panel size. Lights, fans, a fridge, a TV and Wi-Fi for 4 hours take about 1.9 units, which 2 UTL 25.6 V, 100 Ah lithium batteries cover. The same loads through an 8-hour cut need about 3.8 units.

What size hybrid inverter do I need?

Add up the watts of everything on backup that runs at once, then allow for motors starting. The calculator picks the next standard size, from 1 kVA up to 15 kVA. Lights, fans, a fridge and a TV fit a 1 kVA inverter.

Can a hybrid system run an AC during a power cut?

It can, but the battery gets much bigger. Adding one 1.5 ton inverter AC to a 4-hour cut takes the battery from about 1.9 to 5.5 units and the system to 3 kW. Most homes keep ACs on the grid and back up lights, fans and the fridge.

Lithium or tubular for a hybrid system?

Tubular costs less to buy and suits a system that only uses the battery during occasional cuts. Lithium lasts about twice as many cycles, weighs far less and needs no water, so it pays off where cuts are daily.

Does a hybrid system get the PM Surya Ghar subsidy?

Yes. Our hybrid systems stay connected to PSPCL through a net meter, so they qualify the same way as on-grid, up to ₹78,000 for a home. The subsidy does not cover the battery.

How much roof does a hybrid system need?

About 100 sq ft of shade-free roof per kW of panels, the same as on-grid. A 3 kW hybrid system needs about 300 sq ft.