Off-Grid Solar
Questions,Answered

We design your system based on your property’s expected maximum occupancy to protect its resale value and prevent costly upgrades later. For a typical family home, we calculate your energy needs by allowing 5 kWh per day for the house itself, plus an additional 5 kWh per person.

For example, a fully occupied 5-bedroom home with up to six people would require a system capable of handling about 35 kWh per day. Our systems are built to provide 48 hours of battery autonomy and rely on conservative winter solar estimates so you can live comfortably without relying on a noisy generator

Reliability is our main objective, which is why our larger systems feature a dual-system design. We build setups with parallel components, such as using dual inverters and split battery banks, so there is no single point of failure. If one inverter or battery goes offline, the rest of the system continues to operate independently. While the system will run at a reduced capacity, this redundancy ensures that power to your home is not interrupted while the issue is being repaired

Yes, we offer flexibility in the equipment we install. While we typically supply trusted solar panels from Jinko or Aiko, you can request any alternative brand of your choice. For inverters and batteries, we frequently recommend platforms like Sigenergy, Deye, Victron, and Solis, but we can source other reliable brands if requested. We only recommend equipment that has proven reliability in harsh Australian conditions, such as locally made modular systems from XESS Energy or high-quality lithium batteries from Pylontech, BYD, and PowerPlus

High-voltage lithium batteries (120V–800V) are ideal if you have a large solar system and plan to run heavy loads like air conditioners, pool pumps, or electric vehicle chargers. They operate with much less current than older 48V systems, meaning they require thinner cables, lose less energy as heat, and offer better round-trip efficiency. Because they can handle larger amounts of power without overloading the system, they provide faster charging and discharging during blackouts. However, if you have a smaller cabin setup, a standard 48V system might still be the most cost-effective choice

Yes, off-grid systems still qualify for several government incentives in Australia. Federal Small-scale Technology Certificates (STCs) apply equally to off-grid solar and battery installations, giving rural and off-grid households the same upfront discounts as grid-connected homes. Depending on your location, you may also be eligible for state-specific support, such as the Cheaper Home Batteries Program or zero-interest loans and battery rebates offered in regions like Victoria and New South Wales

Yes. A properly sized off-grid system is built for normal, full-time living — including regional Victoria winters and seasonal swings.

At 100UP we size differently to many grid-tied installers. We don’t audit every appliance or expect you to ration usage. We match inverter capacity and battery headroom to real household loads — cooking, heating, hot water, several appliances running at once.

You live normally. The system handles the rest.

Yes. High-voltage battery banks paired with correctly sized inverters handle surge loads from heating, hot water, air conditioning, and everyday appliances — without rationing or load-shedding.

100UP sizes for maximum occupancy and realistic load patterns, not minimal usage. Your heating, hot water, cooking, and daily power draw run as you’d expect in a grid-connected home.

For hot water we typically specify heat pump technology — lower daily kWh demand with reliable hot water year-round.

100UP uses a straightforward sizing rule: 5 kWh for the house, plus 5 kWh per person based on bedroom capacity — the 100UP Way.

That ties system size to occupancy and winter performance, not annual averages or nameplate ratings alone. Examples:

• 1-bedroom property: 10 kWh/day baseline
• 2-bedroom property: 20 kWh/day baseline
• 4-bedroom property: 30+ kWh/day for full family occupancy

We then model worst-case winter for your location — June/July cloud, short daylight — not best-case summer production.

Winter sizing is the engineering call that decides whether the system works through a Ballarat July or merely looks good on paper.

100UP designs for worst-case winter — not as a margin guess, but as the baseline that sets array size, battery autonomy, and backup strategy.

During extended cloud in regional Victoria winters, three layers work together:

1. Oversized solar array — sized to harvest maximum power in brief 1.5–2 hour winter sun windows
2. Battery autonomy buffer — typically ~48 hours stored energy so consecutive low-production days don’t force generator use
3. Generator as backup — auto-starts only if solar and battery reserves are depleted; rare on a well-designed system

On a correctly sized regional VIC install, generator runtime stays minimal — often zero in normal winters, higher only on demanding sites or heavy occupancy.

It depends how you use the property and how much generator noise, fuel, and maintenance you’re willing to live with.

A smaller system plus generator can work when:

• Weekend or occasional use — you arrive to charged batteries and run the generator rarely
• Occupancy is light and predictable

A full off-grid system makes sense when:

• You live there full-time or for extended stays
• Guests or Airbnb rotation won’t accept power rationing
• Resale value matters — a complete system is an asset; a minimal setup often isn’t

100UP specialises in generator-free normal operation. If a generator is included, it’s emergency redundancy — not a weekly crutch.

Installed cost varies with system size, site conditions, component choice, and installation complexity.

Typical installed ranges (equipment + installation):

• 1-bedroom: $35,000–$45,000
• 2-bedroom: $45,000–$60,000
• 3-bedroom: $60,000–$75,000
• 4-bedroom: $75,000–$100,000+
• 5-bedroom: $100,000–$150,000+

Structural work, earthworks, and permits are quoted separately. Off-grid costs more than grid-tied solar plus battery — it’s an investment in independence when grid connection is expensive or unavailable ($25K–$100K+ on remote blocks before a panel goes up).

Tell us your property, occupancy, and priorities — we’ll model a detailed estimate.

Modern modular platforms — Sigenergy among them — are built to grow with the property.

Battery expansion: Extra modules can be added within roughly the first 1–3 years while models stay compatible.

Solar expansion: More panels on available roof or ground-mount space without re-engineering the core inverter layout.

EV charging: Bidirectional DC chargers can charge from daytime solar and, where the vehicle supports it, feed the home during low solar or peak evening load.

Expansion works when the system is sized with growth in mind upfront — oversized array (cheap), modular battery bank (expandable). That’s how you add EV load or family size without starting over.

Yes — both can be added, but timing and platform choice matter.

Solar panels: Add anytime to available roof or ground space; new strings tie into existing inverter capacity.

Batteries: Plan additions within about three years — after that, specific models may be discontinued and compatibility gets harder.

100UP’s usual approach: oversize the solar array upfront (cost-effective, maximises rebates) and install a lean battery bank for current needs. You harvest more power now and add storage when budget or load increases — without a full redesign.

It depends on architecture.

Single-inverter systems: One failed inverter takes everything offline until repair. We don’t recommend that layout for permanent off-grid homes.

100UP redundant layouts: Parallel inverters (TwinGuard dual, TripleShield triple) isolate a fault — remaining units carry critical loads while you arrange service.

Modular batteries: Each module has its own BMS; one fault doesn’t collapse the whole bank.

Off-grid, total loss of power isn’t an inconvenience — it’s daily life interrupted. Redundancy means reduced capacity, not a black house.

On 100UP installs for full-time or high-value use, redundancy is standard — not an optional extra.

TwinGuard: Dual independent inverters in parallel — one fails, the other carries load.

TripleShield: Three independent inverter/battery sections — no single component owns the whole system.

Modular batteries: Per-module management so one unit fault doesn’t shut the bank.

Without redundancy, one inverter or battery fault blacks out the property. With it, you get reduced capacity, not zero power. That trade-off costs more upfront — and it’s what full-time off-grid living needs.

Current off-grid platforms include cloud monitoring — generation, consumption, battery state of charge, and alerts — without needing an engineering background to read them.

Typical capabilities:

• Real-time solar generation and household load
• Mobile apps (e.g. Sigenergy mySigen, Victron VRM)
• Remote diagnostics before a site visit
• Automated alerts on low battery or component faults
• Generator auto-start at a set state-of-charge threshold

Depending on platform: load scheduling, EV charge optimisation, smart-home integration, and historical performance data.

We specify platforms that give useful visibility — enough to understand performance, not so much complexity you ignore the dashboard.

100UP supports Ballarat and regional Victoria installs after commissioning.

How it works:

• Remote monitoring — many faults diagnosed before a truck roll
• Phone and email — technical questions and performance troubleshooting
• Local service partners — technicians for on-site repair when needed
• Warranty coordination — we clarify manufacturer coverage and handle claims

Business-hours support with emergency contact for urgent issues affecting daily living. Batteries and inverters typically carry ~10-year manufacturer warranties — we’ll tell you what’s covered upfront.

Yes. Off-grid systems connect to a secure cloud platform over Wi-Fi or mobile data so you can check status from anywhere with internet.

Remote visibility includes: battery state of charge, live generation and consumption, performance trends, alerts, and historical data.

For weekenders, holiday homes, and investment properties, that means verifying the system before you arrive and catching faults without an unnecessary site visit.

For full-time homes, it shows how the property actually uses power — useful for understanding patterns, not for micromanaging every switch.

Split solar from storage in the sizing decision.

1. Oversize the solar array now — panels are relatively cheap; fill available roof and ground space
2. Install a lean battery bank — size for current occupancy plus a modest buffer; batteries are the expensive layer
3. Choose a modular platform — add battery modules later without replacing inverter infrastructure

Example: a 3-bed property might launch with 15 kW solar, 54 kWh storage, and 16 kW inverter capacity — then add battery modules when occupancy rises or EV charging lands. Solar and inverter headroom are already there.

You buy flexibility now without paying for kWh you don’t need yet.

Yes. Modern off-grid systems need little attention when the property is vacant. Solar keeps the battery topped up; the BMS balances cells — no manual wake-up routine.

Before you travel, check remote monitoring: state of charge, recent production, any alerts. You arrive knowing power is ready.

Unlike some legacy setups, there’s no awkward cold-start — depending on configuration, the system is already live or one switch away.

That’s why weekender and short-stay properties suit off-grid well — the system works between visits without babysitting.

If you might add an EV, more appliances, more people, or heavier heating/cooling in the next 3–5 years, plan expansion now — retrofitting an undersized platform costs more than sizing the infrastructure correctly upfront.

Prevention approach:

• Modular inverter/battery platform (e.g. Sigenergy) that accepts add-on modules
• Oversized solar array for future load
• Battery sized for today, expandable tomorrow

Simpler only makes sense when usage is genuinely stable — no family change, no EV, no new heavy loads. Most households grow energy demand over time.

100UP’s default: plan for expansion. Lower cost now, fewer expensive regrets later.

Yes. Every 100UP system is sized for maximum occupancy — not just who’s living there today.

The 100UP Way: 5 kWh for the house, plus 5 kWh per person by bedroom capacity. A 4-bedroom install is engineered for up to eight people — heating, hot water, cooking, appliances running together.

That covers family visits, Airbnb guests, changing household size, and resale — a buyer isn’t inheriting a system that only worked for two people.

Full house, full load — that’s the scenario we design for.

Yes — where the vehicle and charger support bidirectional (vehicle-to-home) operation.

A V2H charger lets the car battery feed the home during extended cloud, peak evening cooking load, or when the home bank is low — then recharge from solar when production returns.

Not every EV or charger supports this yet. Check vehicle spec and charger compatibility before assuming V2H.

On large 5-bed properties with events or extended family, an EV adds a meaningful second storage reserve beyond the home battery bank — worth planning into system design as the technology becomes more common.