iTel inverters,
batteries & solar.
A plan for your home.

Three parts. Three different jobs.

The inverter turns DC energy from your battery or panels into AC electricity for your appliances. Its output rating limits how much power you can use at once. The battery stores energy for later. The panels generate energy when the sun is available.

A 6kW inverter with a 5.12kWh battery is not a “6kW battery system that lasts six hours.” At a 1kW load, 5.12kWh × 80% usable depth × 90% efficiency gives about 3.7 hours before accounting for idle draw, ageing and other limits. At twice the load, the energy runs out roughly twice as quickly.

And capacity alone is not enough: the battery’s permitted discharge current must also support that load. A large inverter paired with a small battery can still trip.

“One AC” is not a power specification.

Start with the exact indoor and outdoor model numbers. Then find the electrical input power, rated or maximum input current, voltage, compressor technology and starting data. An AC’s HP label and its cooling capacity in BTU/h or thermal kW do not tell you its electrical input watts.

What do running amps and starting amps mean?

Running current describes operation. Starting current describes a brief event. For single-phase AC, watts = volts × amps × power factor; multiplying volts by amps alone gives VA. Locked-rotor amps (LRA) are a compressor reference condition, not a complete measurement of the installed AC’s start profile.

The planner carries running W and VA, starting W and VA, and start duration separately. Generic AC defaults are editable estimates. If a product lists only cooling output, or has conflicting electrical values, we do not turn those into a “verified” running or start current.

Plan the AC schedule, too.

Two ACs used for eight hours each are a different battery requirement from one AC in a bedroom for four hours. “Average use” models compressor modulation or cycling; it reduces energy, never the inverter’s peak power requirement. For conservative sizing in hot weather, test 100% average use.

Choose a battery for energy and current.

Compare batteries in kWh. Amp-hours need a voltage: 100Ah at 12.8V is 1.28kWh; 100Ah at 51.2V is 5.12kWh. They are both “100Ah” and store very different amounts of energy.

Then match the inverter’s battery voltage family, permitted operating voltage, BMS communication and charge/discharge current. A 24V inverter is not a match for a 48V battery. Parallel identical batteries add energy and current capability while keeping the voltage the same, subject to the manufacturer’s limit and an approved installation.

Why the battery check uses a low voltage

To deliver the same AC watts, a battery supplies more amps as its voltage falls. Checking only nominal voltage can make a system appear capable near full charge and fail near empty. Our shortlist checks steady current at the battery’s published minimum voltage, with your efficiency, idle draw and power headroom included.

Why we leave a reserve

The default plan uses 80% of nominal capacity and a separate 90% capacity-retention allowance. This leaves room for reserve and reduced capacity as the battery ages. It is a planning choice, not a claim that all iTel batteries have the same permitted depth of discharge or ageing rate.

Battery cycle-life claims depend on test conditions. They do not promise a fixed number of years for every home. Heat, deep discharge, charge settings and frequent cycling all matter.

Band A is useful context. Your outage pattern sizes the battery.

NERC describes minimum daily service levels of 20, 16, 12, 8 and 4 hours for Bands A, B, C, D and E respectively. Those figures do not tell us whether your outages arrive as one long block or several shorter cuts. They also do not specify the time or quality of supply. NERC service-band reference ↗

Record actual daily grid hours and the longest outage you want to cover. With only three hours of stable grid charging, a battery may need a much higher charge rate than with ten hours. Adding a bigger battery does not make a small charger refill faster.

Grid + battery can suit short outages with reliable charging. Solar + grid adds another charging source. Solar only requires an energy plan for poor-weather periods as well as your normal day. Enter your own tariff in the planner to compare grid energy costs. Solar may reduce purchases; a battery charged from the grid can increase them while giving you more hours of power. Savings depend on when you use energy and when the grid is available.

Four peak-sun-hours are not four hours of daylight.

Sun intensity changes throughout the day. Peak-sun-hours express the day’s solar energy as an equivalent number of hours at 1,000W/m². Twelve hours between sunrise and sunset do not mean twelve hours at a panel’s nameplate output.

Location, season, orientation, shading, heat and system losses change output. Use a site assessment and monthly solar-resource data for a final design. The planner’s four-hour default is a scenario; it is not a location-specific forecast. Global Solar Atlas ↗

Panels need to run your home and refill the battery.

If panels generate 10kWh and daytime use takes 7kWh, less than 3kWh remains to store after charging losses. A battery sized for a long night may never return to full unless generation or charging capacity increases, or demand decreases.

Panel wattage is only the first screen.

The inverter must accept the array’s power, starting voltage, hot operating voltage, cold open-circuit voltage, operating current and short-circuit current on each MPPT. Bifacial panels can exceed their front-side current. Two panels with similar watts can have different electrical compatibility.

Our panel counts are energy estimates with the existing guide’s partial voltage/current screen. A count is not an approved series/parallel wiring plan. Missing model suffixes and electrical data stay visible.

The maths behind your plan.

Matching products means checking published continuous watts and VA, whichever surge dimension is documented, battery voltage, low-voltage sustained current, battery count limits and the available PV screen. Undocumented surge dimensions, battery transient response and exact BMS pairing remain installer checks. Three-phase systems require a phase-by-phase assessment.

Compare running costs and the purchase separately.

The cost worksheet compares your current grid purchases and the generator fuel budget assigned to these appliances with the proposed system. Fuel spending starts with your actual cost per generator-use day, multiplied by use days and the relevant share of the budget. The reduction you choose is a scenario to check with a fuel log; solar kWh alone cannot predict fuel saved.

One month uses 30 days, six months 180 days, and one year 365 days. These repeat the same routine and prices, so they are not seasonal forecasts. A lower running bill can still cost more overall in the first year: equipment, installation and a maintenance/replacement budget must also be paid for. Add an itemised quote to see that comparison and a conditional simple break-even estimate. Plans with unresolved energy or charging gaps do not receive a comparable-savings claim.

Take a clear plan to your installer.

Download your appliance schedule and shortlisted products. Confirm the exact product revisions, available supply current, circuit separation and simultaneous motor starts. The installer should verify battery communication, permitted current settings, protection, earthing, isolation, cable sizes, ventilation, mounting and roof structure.

PV and battery circuits can carry dangerous voltages and currents. This guide explains planning; installation belongs with a qualified professional. Budget for protection, cabling, mounting, delivery and labour as well as the inverter, battery and panels.

Before you decide.