The right inverter capacity for your home is decided by two independent numbers, not one. The VA rating decides how many appliances can run at the same time. The battery capacity in watt-hours decides how long they run. Most buyers compare only the first, which is why so many homes end up with an inverter that carries the load fine and dies after an hour. Choosing well means measuring your simultaneous load, then choosing a battery sized to the hours you actually need.

TL;DR: VA and watt-hours are separate specifications and you have to size both. A 1000VA inverter delivers roughly 800W of simultaneous load at a 0.8 power factor, and a 1,280Wh battery running that full 800W lasts about 1.6 hours. Buying a higher VA rating inside the same product line usually gets you more simultaneous load on the same battery, not more backup time. Ampere-hours cannot be compared across products unless you also know the pack voltage. Work from the nameplates on your own appliances rather than from a generic wattage table.

What “inverter with battery” actually means, and why the answer changed

There are two things sold under this phrase and they are not equivalent.

A conventional inverter plus battery is two boxes. You buy an inverter rated in VA, then separately buy a battery rated in ampere-hours, and you are responsible for matching them. Most Indian homes have run this arrangement for two decades. Our complete lithium inverter buyer’s guide covers the standards, lifespan and heat-tolerance side of that choice in detail.

An inverter with an inbuilt battery, sometimes called a home energy storage system, is one wall-mounted unit with the inverter, the battery and the battery management electronics integrated and matched at the factory. Truepower’s Lithvon range is built this way.^[1]

The practical difference is who owns the matching risk. With two boxes, a charge profile mismatch between inverter and battery is your problem and it usually shows up as premature battery failure. The chemistry behind that failure mode, and how lithium and lead-acid differ on it, is covered with sourced research in our LiFePO4 versus lead-acid tubular comparison. With an integrated unit, the manufacturer has already matched them, and the warranty covers the pair rather than pointing at the other component.

That integration is also why capacity selection works differently. You are no longer picking a VA number and an Ah number separately from two catalogues. You are picking a configuration, and you need to understand what each configuration actually gives you.

The two numbers that decide capacity, and how they differ

VA rating decides simultaneous load. Volt-amperes measure apparent power. To convert to the watts your appliances actually draw, multiply by the power factor, which is 0.8 across the Lithvon range. So a 1000VA unit supports about 800W running at once, and a 3000VA unit supports about 2,400W.

Watt-hours decide duration. A watt-hour is one watt drawn for one hour. Divide the battery’s watt-hour figure by your actual load in watts and you get hours of backup, before real-world losses.

The arithmetic is deliberately simple. A 1000VA inverter carrying its full 800W, paired with a 1,280Wh battery, runs for 1,280 ÷ 800 = 1.6 hours. Halve the load to 400W and the same battery runs about 3.2 hours.

That relationship is the whole of capacity selection. Everything else is detail.

Two things routinely trip buyers up here. Nobody runs full rated load continuously, so the pessimistic figure above is a floor rather than a forecast. And a small standing draw exists even with nothing switched on, which the Lithvon specification sheet lists as under 2.5A no-load current.

Why a bigger VA rating usually will not give you longer backup

This is the single most expensive misunderstanding in the category, and Truepower’s own catalogue demonstrates it cleanly.

The Lithvon Home ESS is offered at 1000VA and 1250VA. Both carry the same 1,280Wh battery.^[2]

The Lithvon Pro Home ESS is offered at 2000VA, 2500VA and 3000VA. All three carry the same 2,560Wh battery.^[3]

Read that again, because the implication is counterintuitive. Stepping from 1000VA to 1250VA inside the Home ESS line buys you roughly 200W more simultaneous load and not one extra minute of backup at a given load. Stepping from 2000VA to 3000VA inside the Pro line buys you roughly 800W more simultaneous load, again on an identical battery.

Backup time only increases when the watt-hour figure increases, which in this range means moving from the Home ESS tier to the Pro tier, where the battery doubles from 1,280Wh to 2,560Wh.

So the selection logic runs in this order. Establish your simultaneous load first, because that sets the minimum VA rating and you cannot compromise on it without tripping the overload protection. Then establish your required hours, because that sets the watt-hour tier. Buying VA headroom you do not need is spending money on a capability that does nothing for the complaint most people actually have, which is that the power runs out too early.

Why “100Ah” tells you almost nothing on its own

Indian buyers shop for batteries in ampere-hours. It is the number on every tubular battery sold in the last thirty years. It is also close to useless for comparing lithium products, and the Lithvon range shows exactly why.

Both Lithvon packs are 100Ah. The Home ESS holds 1,280Wh at 12.8V. The Pro holds 2,560Wh at 25.6V. Divide either watt-hour figure by its voltage and you get 100Ah both times.

Same ampere-hours. Double the stored energy. The difference is entirely voltage, because watt-hours equal ampere-hours multiplied by volts.

The practical rule: an Ah figure quoted without a pack voltage is not a specification, it is a marketing number. Ask for watt-hours, or ask for the voltage so you can work them out. Any seller who cannot supply one of the two does not have a datasheet.

Which inverter capacity fits your home?

Start by measuring rather than guessing. Every appliance carries a nameplate, usually on the back or underside, stating its wattage or its current draw in amps. Add up only the things that would genuinely run together during an outage. Then check your last electricity bill for monthly units, which tells you what your household consumes overall.

Motor loads need one extra step. Anything with a compressor or a pump, a refrigerator, a water pump or an air conditioner, draws a brief starting spike well above its running figure. Published multiples for that spike vary so widely across sources that quoting one would be misleading, so the sound approach is to read the starting current from the appliance nameplate where it is given, and to leave headroom rather than sizing to the running figure alone.

Against that measured load, the range maps as follows.

The Home ESS tier suits a household running lights, fans, a television and routers through an outage. The Pro tier suits a household that also wants a refrigerator and a water pump covered, or that needs the same load carried for roughly twice as long. The KIVO tier is a different decision entirely, because it adds MPPT solar charging and is chosen when the goal is cutting the bill rather than only surviving the cut.^[4]

For how these price bands are built up and what drives them, see our lithium inverter price breakdown. Prices and availability change, so verify on the product page before ordering. Several other inverters in the Truepower catalogue were showing out of stock on the observation date and are not included above.

Five things to check before you buy an inverter with battery

The input voltage window. This decides whether the unit keeps charging during the brownouts that precede most Indian outages. The Lithvon Home ESS specification lists a normal-mode input range of 100V to 285V, which is wide, and a narrower 180V to 265V window in UPS mode. A unit that stops charging at 180V in an area that sags to 150V will meet every outage with a part-charged battery.

The protection list, item by item. The Lithvon Home ESS publishes reverse battery, overload, battery low, battery high, short circuit, input high and low voltage, and overheat protection. Ask for this list in writing rather than accepting “fully protected”, because the omissions are what matter.

Warranty on the inverter and the battery separately. These often differ and the difference is material. Both Lithvon Home ESS and Lithvon Pro Home ESS carry five years on both. Full terms are in the Truepower warranty policy.^[5]

What installation actually costs. Truepower lists free shipping, DIY installation and on-site service against both Lithvon products. On a purchase around ₹29,000 that is not a rounding error, and comparing sticker prices without it understates the gap against sellers who charge separately.

Whether solar is in your plans. A standard lithium inverter has no solar input, so adding panels later means replacing the unit rather than extending it. However, Truepower is also working towards incorporating solar into the product.

Related reading

Lithium Inverter for Home: The Complete Buyer’s Guide

LiFePO4 vs Lead-Acid Tubular Inverter Battery: Which Lasts Longer in India?

Lithium Inverter Price in India: 1000VA to 5000VA Cost Breakdown