AMPAURA AUSTRALIA
Learn

Commercial batteries, explained for busy people

Plain-English answers to the questions that matter before you talk to anyone, including us. No jargon, no vapour numbers, and where a claim has a basis, the basis is stated.

Peak Demand Reduction
Why one half-hour sets your bill
Peak Shaving
How the battery caps it
Self Consumption
Use your solar after sunset
Energy Arbitrage
Buy cheap, use it dear
Blackout Protection
The site stays on
Power Purchase Agreement
No capital: the battery works for the grid
Working mode 01

Peak demand reduction: one half-hour sets your whole month

One week of demand, with and without batteries100200300MonTueWedThuFriSatSunthe daily dips are your existing rooftop solar carrying the sitekW drawn from the gridIllustrative week from real meter data: a Queensland transport depot with rooftop solar already installed.

Commercial bills have two meters running. Energy is what you use across the month. Demand is how hard you pull at any one moment, and it is priced off your single worst half-hour. The network builds its poles and wires for that moment, so that is what it charges you for. Cap the peak, and the charge follows it down.

Demand charges can be 30 to 50% of a commercial power bill
One bad half-hour sets the rate you pay all month
Your energy use does not change, the demand line just shrinks
The full peak demand page →

Where the money hides on your bill

Pull out a recent invoice and find the line priced in kW or kVA rather than kWh. That is the demand charge, and on many commercial tariffs it is set by your single highest half-hour reading of the month. The frustrating part: it does not matter whether that peak lasted thirty minutes or was your only spike all month. The network sized its response to your worst moment, so the price did too.

kWh lines price what you used; kW or kVA lines price how hard you pulled
Some tariffs reset monthly, others hold your peak against you for twelve months
In NSW, cutting peak demand also earns a scheme incentive in its own right
The NSW incentive →

What decides how much you save

Two things: how spiky your load is, and whether the battery has the power rating to carry the spike. A site with a flat load profile has little demand charge to recover. A site whose compressors, welders or chargers all land at once can see the demand line become the biggest saving a battery makes. This is exactly what a load assessment reads out of your interval data.

Find your peak with a load assessment →

A week tells the story a day cannot

The graphic above runs across seven days because that is how demand behaves in the real world. On the live project it is modelled on, the site held a steady load around 240 kW, dipped hard through the middle of each day while solar carried it, then threw a different-sized spike each evening. Only one of those seven spikes set the month's bill. Everything else the site did all week made no difference to the demand line, which is exactly why a battery that watches every half-hour beats any amount of guesswork.

Demand is set by one half-hour, not by how much you use across the week
The dip in the middle of each day is existing rooftop solar carrying the site
Seven evenings, seven different spikes, and only the biggest one counts

One battery or several: choosing how far the cap drops

Storage scales, and so does the saving. On the same live project, one battery was modelled to hold demand near 220 kW. Two brought the cap down to about 146 kW. Three pushed it below 55 kW, taking a site that used to spike past 350 kVA down to a draw the network barely notices. In the mid option, demand charges fell from roughly $72,000 a year to under $30,000. Each extra battery buys a deeper cap and a bigger saving, so the right number is a sizing exercise: we model your actual meter data and show you what each step is worth before you commit to anything.

One battery held the cap near 220 kW, two near 146 kW, three below 55 kW
In the mid option, demand charges fell from about $72,000 a year to under $30,000
The right number is a sizing exercise, modelled on your own meter data

The three flavours of demand tariff

Not all demand charges behave the same way, and the difference changes how much a battery is worth. A monthly peak tariff resets every billing cycle: one bad afternoon costs you one month. A rolling ratchet holds your highest reading against you for up to twelve months: one bad afternoon costs you a year. A capacity charge is agreed in advance: you pay for a fixed ceiling whether you touch it or not, and exceeding it brings penalties. Batteries help with all three, but the ratchet is where they earn hardest, because a single avoided spike keeps paying for twelve months.

Monthly peak: each month is a fresh start, and every month needs defending
Rolling ratchet: your worst half-hour follows you for up to a year
Capacity: stay under the agreed ceiling and consider renegotiating it down once the battery proves itself

What a bad month actually looks like

Picture a cold-storage site on a February afternoon. Compressors are working hard against the heat, a delivery arrives and the dock doors open, defrost cycles land at the same time, and someone switches on the second blast freezer. None of these is unusual. Together they stack into one half-hour reading far above the site's normal ceiling, and that reading becomes the demand charge for the month, or the year. The point of the story: peaks are not caused by waste, they are caused by coincidence. You cannot roster your way out of coincidence, but a battery does not need to. It just needs to be charged when the stack happens.

Common mistakes when chasing the demand line

Adding solar and expecting the demand charge to fall: peaks often land late in the day when solar is fading, so the worst half-hour barely moves
Chasing kWh efficiency when the bill problem is kW: LED upgrades do not stop five machines starting at once
Setting a demand alarm and asking staff to respond: by the time a human reacts, the half-hour is already gone
Sizing the battery on energy use instead of peak shape: the spike height and width set the requirement, not your monthly kWh

Quick answers

Does reducing my energy use reduce my demand charge?

Mostly no. The demand charge only cares about your single worst half-hour. You can cut consumption 20% and still pay the same demand line if your peaks are untouched.

Can I just spread my machine start-ups through the day?

Staggering helps where you control the timing, and it is free, so do it. But most peaks come from coincidence you cannot schedule: weather, deliveries, production surges. The battery covers what the roster cannot.

How do I find out what my peak actually is?

It is in your interval data, which your retailer must provide. Send us twelve months of it and we will show you the exact half-hours that set your bills.

In one sentence: your demand charge is set by your worst half-hour, and a battery exists to make sure the grid never sees it.

Working mode 02

Peak shaving: the battery takes the top off the spike

One day, one spike, no peak12am6am12pm6pm12amDemand thresholdbattery carries thiswhat the day wanted to dowhat the grid actually sawIllustrative day. The grid never sees the spike, so the spike never sets your bill.

This is the physical behaviour behind demand reduction. The system watches your load climb toward a threshold, and the moment it gets close, the battery discharges and carries the difference. The grid never sees the spike. Forecasting matters here: the battery has to be charged and ready before the risk window opens, which is why the plan is rebuilt from fresh forecasts every day.

The battery discharges the moment load climbs toward the threshold
Positioned in advance, because a flat battery cannot shave anything
The threshold tightens over time as AI Mode learns your site
How AI Mode runs this daily →

Why forecasting is the hard part

Shaving a peak sounds like a reflex, but the work happens hours earlier. If the battery is flat when the spike arrives, nothing can be shaved, and if it holds too much back, that energy earns nothing all day. So the system forecasts tomorrow's load, solar and prices, decides when the risk window opens, and makes sure the battery walks into it charged. That plan is rebuilt from fresh forecasts every day, and AI Mode keeps tightening the threshold as it learns how your site actually behaves.

The battery must be positioned before the risk window, not during it
Too cautious wastes the asset; too aggressive misses the peak
The threshold tightens over time as the forecasts learn your site

Power and energy are different jobs

Shaving is a power problem first: the battery's kW rating decides how big a spike it can carry. The kWh rating decides how long it can hold the spike down. A short sharp peak needs muscle; a long afternoon plateau needs stamina. Sizing the system means reading which shape your site produces, which is why we model from your own half-hours rather than a rule of thumb.

How sizing feeds the payback model →

Anatomy of a shave, minute by minute

Hours ahead, the forecast flags a risk window for late afternoon and the plan makes sure the battery walks into it full. As load climbs toward the threshold, the system is watching real readings, not the clock. The moment the trajectory says the threshold will be crossed, the battery starts discharging, and from the grid's point of view the site simply flattens. When the underlying load falls away again, the discharge tapers, and if the tariff allows, the battery quietly recovers charge in the cheap hours that follow. Nobody on site notices any of it, which is the entire point.

Before: forecast the window, position the charge
During: discharge tracks the spike in real time, holding the grid draw flat
After: recover charge at the cheapest safe opportunity, ready for the next one

Back-to-back peaks, the honest hard case

The awkward scenario is two spikes in one afternoon. Shave the first with everything and there is nothing left for the second, which then sets your bill anyway. This is where planning beats reflexes: if the forecast sees both, it rations the shave across them, holding the demand line at the best achievable level for the whole day rather than winning the first battle and losing the war. It is also why battery energy capacity matters, not just power: stamina is what survives the second peak.

Why manual shaving fails

Plenty of sites have tried the human version: a demand alarm, a standing instruction to shed load, a supervisor with a checklist. It fails for boring reasons. The alarm fires mid-half-hour when much of the damage is booked. The person is busy, or on leave, or sheds the wrong thing. And the loads you can safely drop in five minutes are rarely the ones causing the spike. Automated shaving reacts in seconds, needs nobody present, and touches production not at all.

Quick answers

Does shaving interrupt anything on site?

No. The site draws the same power it always wanted; part of it simply comes from the battery instead of the grid. Machines cannot tell the difference.

What if the peak is bigger than the battery?

The battery shaves what it can and the demand line settles at the best achievable level. Sizing against your actual spike history is exactly what the load assessment is for.

How does the system know a peak is coming?

Forecasts built from your site's own history, weather and calendar patterns, corrected against live readings all day. It gets better the longer it runs on your site.

In one sentence: shaving is the battery stepping in for the exact minutes your site would otherwise set a new peak, and forecasting is what makes it reliable.

Working mode 03

Self consumption: your midday solar, used after sunset

Store the midday, spend it in the evening12am6am12pm6pm12amsolarsite loadbatterysurplus storedbattery powers the eveningIllustrative day. The gold surplus goes into the battery, not the grid, and comes back after sunset.

Most commercial solar systems make their best power at midday and spill the excess to the grid for next to nothing, then the site buys expensive power all evening. A battery closes that loop: the midday surplus goes into storage instead of the grid, and comes back out when the sun is gone and the tariff is not.

Excess solar is stored instead of exported for cents
The evening peak runs on your own stored energy
Every stored kilowatt-hour replaces one bought at the evening rate
What a battery does for a business →

Why exporting is a bad deal

Feed-in rates for commercial solar are a fraction of what you pay to buy power in the evening. Every kilowatt-hour you export at midday and buy back at 7pm is the same energy traded at the worst possible exchange rate. Storage flips that: the surplus keeps its full retail value because it never leaves your site. And as networks move to dynamic export limits, there are hours where exporting is not just poorly paid but capped, which makes the store-it case stronger again.

Stored solar keeps retail value; exported solar earns cents
Dynamic export limits can cap what you are allowed to spill anyway
The battery absorbs what the grid will not take

Sizing the store to the surplus

The right battery size falls out of two curves: how much solar you spill at midday, and how much load you carry after sunset. Too small and you leave surplus on the table; too large and capital sits idle. Designer reads both curves from your interval data and sizes the system where they meet.

How Designer sizes a system →

Your meter has a duck curve too

The famous duck curve is what solar does to the whole grid: a deep midday dip in demand, then a steep evening ramp as the sun leaves and everyone switches on at once. Your site with solar has a private version of the same shape. Midday, your grid draw collapses and may even go negative. Evening, it surges back exactly when power is dearest. The battery is the tool that flattens your private duck: it swallows the midday dip and feeds the evening ramp, so your grid draw looks calm all day even though your site is not.

Summer surplus, winter honesty

Self consumption is seasonal. In summer the midday surplus is generous and the battery fills easily from your own roof. In winter, shorter days and heavier heating loads can shrink the surplus toward zero, and a battery that only knew one trick would sit underused. This is why the working modes are a portfolio rather than a setting: on thin-solar days the optimiser leans harder on arbitrage and shaving, and the asset keeps earning either way. A battery bought for one mode alone gets judged unfairly by August.

Summer: fill from the roof, spend it after sunset
Winter: the same battery pivots to cheap-grid charging and peak defence
The mode mix changes with the season; the earning does not stop

Battery first, or more panels first?

A common fork in the road. If your existing solar already spills a healthy midday surplus, a battery usually beats more panels: you are wasting energy you already own. If your solar barely covers daytime load, extra panels might come first, or the two together. The wrong answer is guessing. Designer models both paths against your interval data and shows which sequence pays back faster, with the assumptions on the page.

Model both paths in Designer →

Quick answers

Why not just export the surplus and collect the feed-in?

Because the feed-in rate is a fraction of the evening purchase rate. Exporting at midday and buying back at 7pm is trading your own energy at the worst exchange rate on offer.

Is my solar wasted on weekends when the site is quiet?

Without storage, mostly yes: light load means maximum spill. With storage, quiet days become the best charging days, banked for Monday morning's ramp-up.

What happens when the battery is full and the sun is still out?

The system exports what the network allows, within any dynamic export limits, and the optimiser has usually planned the morning so the battery fills late rather than early, leaving room for the afternoon.

In one sentence: self consumption means your own solar keeps its full retail value by being spent on site after dark, instead of being sold for cents at noon.

Working mode 04

Energy arbitrage: buy power cheap, use it when it is dear

Same energy, bought at a better hour12am6am12pm6pm12amcheap windowsolar floods the gridexpensive windowpricechargingdischargingIllustrative prices. The moving line is the time of day: the battery fills in the cheap hours and carries the site through the dear ones.

Electricity prices move through the day, and the gap between the cheapest and dearest hours is the opportunity. In Australia the cheapest hours are now the middle of the day, when rooftop and grid-scale solar flood the market. The battery fills then and carries the site through the expensive evening. No behaviour change on site, no one turns anything off. The saving comes purely from when the energy was bought.

Charge in the cheap middle of the day, when solar floods the market
Discharge through the expensive windows instead of buying
Works alongside shaving and self consumption, not instead of them
Where arbitrage sits in the value stack →

Where the spread comes from

Prices are shaped by supply and demand across the day. Through the middle of the day so much solar is generating that wholesale prices fall to their lowest, and sometimes below zero. In the early evening solar output falls away while businesses and homes ramp up together, and prices spike. That daily spread between the cheap hours and the dear ones is the arbitrage opportunity, and it exists whether you are on a time-of-use tariff or exposed to wholesale prices.

The evening peak is the most expensive energy of the day, almost every day
The midday solar trough is the cheapest, and the battery buys there
Wider tariff spreads mean bigger arbitrage value, so the tariff matters

Arbitrage plays third fiddle, and that is correct

On most commercial sites arbitrage earns less than demand reduction and self consumption, and it should never compromise them: a battery that sold everything into the evening price and then met your peak flat has cost you more than it made. This is exactly the trade-off the optimiser weighs every day, across all objectives at once, so each kilowatt-hour goes where it earns most.

How the optimiser ranks the jobs →

Which tariffs make arbitrage sing

Arbitrage value depends entirely on the spread you can trade across. A flat-rate tariff offers nothing: every hour costs the same, so timing is worthless. A time-of-use tariff offers a dependable daily spread between off-peak and peak windows. Wholesale exposure offers the biggest and wildest spreads, including the occasional price spike where a battery earns a month's value in an afternoon, and negative-price hours where you are effectively paid to charge. The dearer your peak window relative to your cheap one, the more this mode matters to you.

Flat rate: no spread, no arbitrage, other modes carry the case
Time of use: steady daily spread, dependable arbitrage income
Wholesale exposure: the biggest spreads, best captured by automation, not humans

Does daily cycling wear the battery out?

Cycling is what batteries are for, and the LFP chemistry in our systems is rated for thousands of full cycles under warranty. The real question is whether a given cycle earns more than it costs in battery life, and that is not a judgement a human needs to make at 6pm: the optimiser weighs the value of each discharge against degradation and warranty terms as part of the daily plan. Thin spreads that are not worth a cycle simply do not get chased.

When arbitrage leads the case

Third fiddle is the usual seat, not the permanent one. Sites with a flat, steady load and little demand charge, sites without solar, and sites on aggressive time-of-use or wholesale pricing can all see arbitrage climb the order. Sites that run hardest in the evening are the classic case: they buy most of their power in the dearest window, so shifting that consumption onto midday energy is where the widest spread sits.

Quick answers

Is this trading? Do I need to watch prices?

No. The optimiser reads the prices and plans the cycles. You see the result in the monthly report, not a trading screen.

Could the battery sell everything and leave me exposed?

No. Peak protection and reserve levels outrank arbitrage in the plan. A cycle that would compromise the demand defence does not happen.

Does arbitrage work without solar?

Yes. It is the one mode that needs no solar at all: it trades purely on the difference between cheap hours and dear ones.

In one sentence: arbitrage is buying your energy at the day's cheapest hours to use in its dearest, and it is worth exactly as much as the spread on your tariff.

Working mode 05

Blackout protection: when the grid drops, the site does not

The outage your site never noticed12pm2pm4pm6pm8pmgrid outage, 2pm to 6pmgrid supply: zerogrid supplysite load: uninterruptedbattery carries the siteIllustrative outage, load from real meter data. The grid cuts out; the battery carries the site.

For some businesses the battery's biggest number is not on any bill: it is the outage that did not stop production, spoil the cold room or drop the servers. When the grid fails, the system islands the site and carries the critical load until the grid comes back, then reconnects cleanly.

Critical load carried from the moment the grid drops
Solar can keep charging the battery during a long outage
Clean reconnection when the grid returns, no manual switching
The hardware that does this →

Whole site, or just what matters

Backup is a sizing decision. Carrying an entire facility through a long outage takes serious capacity; carrying the circuits that actually cost you money, the cold rooms, the servers, the controls, the security, takes far less. Most sites land in between: the battery islands the site, sheds what can wait, and holds what cannot. That priority list is set during commissioning, with you, not discovered during the first blackout.

Critical circuits defined up front, shed lists agreed in commissioning
Solar keeps recharging the battery during a long daytime outage
Backup capacity still earns on every normal day, unlike a generator

What an outage actually costs

The bill savings from the other four modes are easy to model. Outage value is lumpier: spoiled stock, stopped production, restart labour, missed orders, and the occasional insurance excess. If your business has ever added up a blackout afternoon, you already know whether this mode matters to you. Bring that number to a load assessment and we will size the backup case honestly alongside the savings case.

Talk through your outage risk →

How islanding actually works

Grid-connected inverters normally follow the grid's rhythm. When the grid disappears, an islanding-capable system does two things fast: it disconnects the site at the point of supply, so it never backfeeds a dead network, and its inverter switches from following the grid to forming one, setting the voltage and frequency for the site itself. Your equipment keeps seeing normal power because, inside the fence, the battery has become the grid. When utility supply returns and holds stable, the system synchronises and reconnects without anyone touching a switchboard.

Disconnect at the point of supply, never backfeed the network
The inverter forms the site's own grid, batteries as the source
Resynchronise and reconnect automatically when supply is stable again

Long outages: solar and generators join in

Battery capacity buys hours. For outages that run longer, the islanded site can keep harvesting: solar continues charging the battery through the day, stretching the reserve well beyond its nameplate hours. Sites with an existing generator can integrate it as the backstop: the genset charges the battery and supports load while the battery handles the instant response and smooths the ride. That combination beats a generator alone, which takes seconds to start and hates partial loads.

The reserve is a decision, not an accident

A battery that earned all day and sat empty at 6pm would be useless in an evening blackout. That is why backup reserve is an explicit setting: a slice of capacity the daily optimisation is not allowed to touch. Protecting that reserve is one of the objectives the optimiser weighs every day, so the earning happens with the insurance intact. How big the slice should be is a conversation about your site: what must stay on, for how long, and what an outage costs you.

Quick answers

Will the lights even flicker when the grid drops?

The changeover is fast enough that most equipment rides through it without noticing. Truly zero-gap requirements, like some medical or data loads, are a specific design conversation, so raise them early.

Does backup mean I lose the daily savings?

You trade a slice, not the lot. The reserved capacity sits ready while the rest of the battery keeps earning through the other four modes.

Can the whole site run on battery?

If it is sized for that, yes. Most sites choose to back critical circuits instead, which is far cheaper and covers what an outage actually threatens.

In one sentence: blackout protection means your site forms its own grid the moment the network fails, running the loads you chose to protect until supply returns.

Funding model 06

Power Purchase Agreements: the battery without the capital

In front of the meter: the battery works for the gridYOUR SIDEGRID SIDEthe meter$0 capital requiredYour businesshosts the system: nothing to buy, nothing to operateGrid batteryowned and run by the funderThe gridbuys low, middaysells high, evening peakBattery responds to the market in secondsyour benefit flows through the contract: lease income or cheaper energyIllustrative. The battery trades with the grid and holds frequency; the business hosts it, capital free.

Every other tab on this page describes a battery you own, working to cut your bill. A Power Purchase Agreement flips the model: a funder owns, insures and operates the system, you provide the site and the grid connection, and no capital leaves your business. In most of these deals the battery sits in front of the meter, on the grid side of your connection point, and that changes everything about what it does all day.

No capital required, by design

Under a PPA or lease structure, the owner pays for the hardware, the installation, the insurance and the maintenance for the life of the agreement. Your business signs a long-term contract instead of a purchase order: typically you either buy the energy the system produces at an agreed rate, or you are paid rent for hosting the asset on your land and connection. Your balance sheet stays clean, and the performance risk sits with the party who owns the machine.

Zero upfront cost: the funder carries hardware, install and operations
Terms usually run 7 to 15 years, with the asset owner responsible for performance
Your business hosts the system and gets paid, or buys its output at an agreed rate

In front of the meter: whose side is the battery on?

Everything else on this page is behind the meter: the battery sits on your side of the connection, your loads see it, and it earns by changing your bill. An in-front-of-the-meter battery connects on the grid side. It is registered as a market asset, the market operator can see it, and your site's loads never draw from it directly. Same hardware, completely different job description.

What an in-front-of-the-meter battery actually does

It earns from the electricity market itself. Energy arbitrage at wholesale scale: charging when prices are low or negative in the middle of the day, discharging into evening peaks when the grid is short. FCAS, the frequency control ancillary services: the battery is paid to stand ready and respond within seconds when grid frequency drifts, injecting or absorbing power to hold the system at 50 hertz. And network support: soaking up local solar exports and easing congestion so the network can defer building poles and wires.

Wholesale arbitrage: buy the midday trough, sell the evening peak, every day
FCAS: paid to respond in seconds when grid frequency moves, often the largest revenue stream
Network support: absorbing local solar and deferring grid upgrades

In these deals, the battery is not there for you

This is the mindset shift. An in-front-of-the-meter battery does not shave your peaks, does not back up your site in a blackout, and does not care what your factory is doing. It is there for the grid: trading energy, holding frequency, supporting the network. Your benefit arrives through the contract instead: lease income for hosting it, or energy at a better price than your retailer offers, with none of your capital at risk. If you want the battery working for your site as well, that is a different design, and we model both so you can compare them on numbers rather than instinct.

In one sentence: with a PPA, someone else pays for a battery that works for the grid rather than your site, and you earn from hosting it or buy its energy cheaper, with no capital outlay.

Topics

Start with the question you actually have

Why is my bill so high?

Demand charges can be 30 to 50% of a commercial bill, and one bad half-hour sets them. Here is how that works and how a battery caps it.

Peak demand reduction →
What does it actually return?

Most C&I sites land between 4.5 and 7.6 years. What moves a site within that range, what a defensible model includes, and where the value really comes from.

ROI and payback →
What will governments chip in?

From 1 September 2026 the NSW scheme covers commercial batteries, and our systems are certified for it. The rest of the picture, honestly told.

Incentives →
What runs the thing?

The battery is the muscle. The intelligence layer decides when to charge, when to shave and what to chase each day.

Ampaura Connect →
Is it safe, and is it certified?

Cell chemistry, fire suppression, Australian standards and the documents your insurer will ask for.

The hardware →
Will it work with my gear?

Probably. Six brands tested and running today, open protocols, and up to four weeks to onboard something new.

Compatibility →
Want the whole picture in one read?

The commercial battery storage guide covers the full journey: what a battery does for a business, which industries are already benefiting, whether your site is a candidate, and how buying works.

Commercial battery storage, the complete guide →

Have a question these pages do not answer?

Ask it. A person in Adelaide reads these, and if the question is good we will probably write the answer into this section for the next reader too.