Reference · 68 terms · Schema.org DefinedTermSet

Solar + battery glossary

Plain-English definitions for 68 terms an Australian solar buyer is likely to meet in a quote, contract, manufacturer spec sheet or grid-connection form. Drawn from CEC publications, Australian Standards, Clean Energy Regulator material + manufacturer datasheets.

The Community Services Desk · Editorial team, NDIS + emergency plumbing + solar · Updated 17 May 2026 · How we rank · Editorial standards

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Federal scheme + market Industry bodies + accreditation Cell + panel technology Inverters + electrical Grid, tariffs + export Battery + storage Roof + install Heat pumps + EV Energy authorities Financial + paperwork

Section 1

Federal scheme + market

STC (Small-scale Technology Certificate): Tradeable certificate created by every kW of installed solar in the Small-scale Renewable Energy Scheme (SRES). One STC represents 1 MWh of expected generation. Each STC has a market price (typically $35-$40). Installers create + sell STCs and pass the value to you as a point-of-sale discount.
LGC (Large-scale Generation Certificate): Renewable energy certificate created by utility-scale (>100kW) generation. Different scheme to STCs. Residential solar households cannot create LGCs. The scheme funds the Renewable Energy Target.
RET (Renewable Energy Target): Federal scheme covering both small-scale (SRES + STCs) and large-scale (LRET + LGCs) renewable generation. Administered by the Clean Energy Regulator.
SRES (Small-scale Renewable Energy Scheme): The federal subsidy scheme for residential + small commercial solar. Operates by issuing STCs based on system size and zone. Legislatively phases out by 31 December 2030.
CER (Clean Energy Regulator): Federal agency administering the RET, SRES + STC market. Also administers the federal Cheaper Home Batteries program from 1 July 2025. cleanenergyregulator.gov.au.
STC zone: One of four solar resource zones across Australia, set by the Clean Energy Regulator. Zone 1 (top half of NT, far north QLD) is highest, Zone 4 (Melbourne, Tasmania) is lowest. Same-size system attracts more STCs in higher zones.
Deeming period: The number of years of future generation that STCs are paid up-front for. Currently 6 years (2026). Reduces by 1 year each year through to 2030. Means the STC rebate value drops every January.
Federal Cheaper Home Batteries program: Federal battery rebate effective 1 July 2025. ~30% of installed battery cost, capped at ~$372 per usable kWh, max 50kWh per household. Applied as a point-of-sale discount via a CEC-accredited installer with a CEC-approved battery.

Section 2

Industry bodies + accreditation

CEC (Clean Energy Council): Australian renewable energy industry body. Administers the Approved Solar Retailer scheme + New Energy Tech Consumer Code. Maintains approved-products lists for panels, inverters and batteries.
CEC Approved Solar Retailer: Retail business that has signed the New Energy Tech Consumer Code, passes annual audit + maintains a clean complaints record. The higher consumer-protection signal. cleanenergycouncil.org.au/code-of-conduct.
CEC Accredited Installer: Individual installer accredited (post-2024 by Solar Accreditation Australia, previously by CEC) to perform grid-connect solar + battery installs. Required for STC + federal battery rebate eligibility.
CEC Accredited Designer: Individual designer accredited to sign off on the system design (panel layout, string sizing, AS/NZS 5033 compliance). Can be the same person as the installer or different.
SAA (Solar Accreditation Australia): Body administering individual installer + designer accreditation on behalf of the Clean Energy Regulator from 2024 onwards. solaraccreditation.com.au.
NETCC (New Energy Tech Consumer Code): ACCC-authorised industry code covering solar + battery retailer conduct. Approved Solar Retailers must comply. Replaces the older Solar Retailer Code of Conduct.
AS/NZS 5033: Australian Standard for the installation + safety of photovoltaic (PV) arrays. Every grid-connect install must comply. Updated periodically; current edition AS/NZS 5033:2021.
AS/NZS 4777: Australian Standard for grid connection of energy systems via inverters. Covers inverter performance, anti-islanding + grid stability. AS/NZS 4777.2:2020 is the current installation edition.
AS/NZS 5139: Australian Standard for battery installation. Covers physical separation, fire egress, ventilation + emergency isolation for residential batteries.

Section 3

Cell + panel technology

PV (Photovoltaic): Conversion of light to electricity using semiconductor cells. Solar PV is the residential + commercial generation type. (Distinct from solar thermal which uses sunlight to heat water.)
Mono PERC: Monocrystalline Passivated Emitter Rear Contact cell. Dominant residential cell type 2015-2023. Being superseded by TOPCon + HJT in 2024-2026 new product lines.
TOPCon (Tunnel Oxide Passivated Contact): Newer cell architecture replacing PERC. Higher efficiency, better low-light + temperature performance, near-zero LID. Dominant in 2026 residential product.
HJT (Heterojunction): Premium cell architecture combining crystalline silicon with thin-film amorphous silicon layers. Higher efficiency than TOPCon at higher cost. Used by REC + a few others.
HPBC (Hybrid Passivated Back Contact): Premium cell architecture used by LONGi. All electrical contacts on the rear of the panel for higher aesthetic + slightly higher efficiency.
IBC (Interdigitated Back Contact): Premium cell architecture used by SunPower / Maxeon. All contacts on rear face, highest efficiency, premium price.
Bifacial panel: Panel that generates from both front + rear faces. Useful for ground-mount installs over light-coloured surfaces (gravel, concrete). Residential rooftop installs rarely benefit because the rear is mounted against a dark roof surface.
LID (Light Induced Degradation): First-year output loss in some cell types (legacy PERC: 1-3%; TOPCon + HJT: near zero). Factored into the manufacturer warranty curve.

Section 4

Inverters + electrical

Inverter: Device that converts DC output from panels to AC for the home + grid. The most failure-prone system component (typical lifespan 8-12 years, vs panels 25+).
String inverter: Single inverter that handles all panels in series. Cheapest, simplest. Shading on one panel reduces output across the whole string.
Hybrid inverter: String inverter with DC battery port built in. Solar + battery on one unit. Cheaper than separate inverter + battery inverter for battery-ready installs.
Micro-inverter: One inverter per panel. Per-panel MPPT, granular monitoring, one panel failure does not affect the rest. ~20-40% premium over string. Enphase dominates.
MPPT (Maximum Power Point Tracker): Inverter circuit that continuously adjusts operating voltage to extract maximum power from the array. Multiple MPPT inputs allow strings of different orientation or tilt to operate independently.
Inverter clipping: Loss of generation when panel array DC output exceeds inverter rated capacity. Happens on perfect peak hours of summer days. Net annual loss for a 1.33:1 oversize ratio is typically 2-5% of total production.
Oversize ratio: Ratio of panel array capacity to inverter capacity. The CEC allows up to 1.33:1 (e.g. 6.6kW panels on 5kW inverter). Larger ratios usually fine due to clipping economics favouring more panels.
kW vs kWp: kW = kilowatt (power, instantaneous). kWp = kilowatt-peak (panel rated capacity at Standard Test Conditions). Used interchangeably for system size, technically kWp is more correct.
kWh: Kilowatt-hour (energy, over time). 1 kWh = 1 kW for 1 hour. The unit on your electricity bill + the unit panels are measured for production.
DC vs AC coupling: DC coupled = battery shares an inverter with solar (cheaper, more efficient for new installs). AC coupled = battery has its own inverter, retrofits to existing systems. AC coupling is the common retrofit path.

Section 5

Grid, tariffs + export

DNSP (Distribution Network Service Provider): The poles + wires company in your area (Ausgrid, Endeavour, Essential, AusNet, CitiPower, Powercor, Jemena, United Energy, Energex, Ergon, SAPN, Western Power, Aurora, Power Water). Sets connection rules + export limits.
Grid connection: The technical + administrative process of connecting your system to the grid. The installer submits the application to the DNSP. Approvals can take 1-8 weeks depending on the DNSP + system size.
Export limit: The maximum kW the inverter is allowed to push to the grid, set by the DNSP. Residential single-phase commonly 5kW. Three-phase commonly 15kW. Limits enforced via inverter firmware.
FiT (Feed-in Tariff): Rate the retailer pays for solar exported to the grid. 2026 typical range 0-12c/kWh, much lower than 2010-2015 era. State-mandated minimums in VIC, ACT (limited) + TAS.
Time-varying FiT: FiT that varies by time of day. Higher in evening peak windows, lower midday. Synergy DEBS, EnergyAustralia Solar Surge + others offer time-varying options.
Self-consumption: Solar generation used inside the home rather than exported. Worth retail electricity price (30-44c/kWh) rather than FiT (0-12c/kWh). The economic driver behind battery payback.

Section 6

Battery + storage

Battery cycling: One full charge-discharge cycle. Modern LFP batteries warranted to 6,000-10,000 cycles to 70% capacity retention. Residential use is typically one cycle per day.
Round-trip efficiency: Percentage of energy stored that comes back out (the rest lost to heat in conversion). Modern LFP batteries 90-95%. Tesla Powerwall 3 ~89.5%. Older NMC batteries 88-90%.
DoD (Depth of Discharge): How much of a battery’s rated capacity is usable. Modern LFP batteries 100% DoD. Older NMC batteries 80-90% to protect cell longevity.
Battery EOL (End of Life): Industry definition: capacity retention falls below 70-80% of original rated capacity. Most LFP batteries reach EOL after 10-15 years of one-cycle-per-day residential use.
LFP (Lithium Iron Phosphate): Battery chemistry dominant in 2026 residential storage (BYD, Sungrow, AlphaESS, Sigenergy). Safer (lower fire risk), longer cycle life than NMC, slightly lower energy density (so larger physical size for same kWh).
NMC (Nickel Manganese Cobalt): Higher energy density battery chemistry. Tesla Powerwall 2 used NMC. Higher fire risk than LFP. Largely superseded by LFP in residential storage 2024+.
VPP (Virtual Power Plant): Aggregation of residential batteries dispatched as a single grid resource. Operators pay you for kWh discharged on demand. Major VPPs: AGL VPP, Tesla VPP (SA), Origin Loop, EnergyAustralia.
Backup-ready: Battery + inverter configured to power the home during a grid blackout. Default install is grid-parallel-only (no blackout cover). Add backup gateway + correct wiring at ~$1,500-$3,000 extra.
Anti-islanding: Inverter safety function that disconnects from the grid (and from your home) during a blackout to protect grid workers. Required by AS/NZS 4777. Backup configurations override this with isolated micro-grid mode.

Section 7

Roof + install

Tilt + orientation: Tilt = roof pitch (Australia optimum ~28-32 degrees). Orientation = direction the array faces (north optimum). East-west splits trade 10-15% production for better midday-to-evening generation curve.
Shading: Trees, chimneys, vents or neighbouring buildings blocking sunlight. Even small shading on one panel can reduce output across an entire string in a string-inverter setup. Micro-inverters or DC optimisers mitigate.
Soiling: Dust, bird droppings + pollen on panels. Typical Australian losses 1-3% per year, cleared by rain in most regions. Manual cleaning generally not cost-effective unless near coast, dusty rural roads or under specific trees.
Mounting (tin / tile / klip-lok): The bracket system attaching panels to your roof. Tin (corrugated metal): straightforward + cheapest. Klip-lok: specific clip-fix system. Tile: requires careful tile lifting + waterproof flashing. Slate or thatch roofs: specialist install.
Isolator: DC + AC isolation switches required by AS/NZS 5033. Rooftop DC isolator + main switchboard AC isolator. Provides emergency electrical isolation for firefighters + maintenance.

Section 8

Heat pumps + EV

Heat pump hot water: High-efficiency water heater (300-400% efficient vs 100% for resistance electric or 80-85% for gas). Pairs well with solar by running midday from excess generation. Federal STC + state rebates apply for replacing gas / electric.
EV charger: Home electric vehicle charger. Residential typically 7-22kW. Pairs with solar via "solar surplus" mode (only charges from excess midday generation). Brands: Tesla Wall Connector, Wallbox, Schneider, Zappi.
Bidirectional charger: EV charger that can also discharge the car battery back into the home or grid (V2H / V2G). Limited 2026 availability. Compatible cars + chargers required.

Section 9

Energy authorities

AEMO (Australian Energy Market Operator): Operator of the National Electricity Market (NEM) + Western Australian Wholesale Electricity Market. Forecasts demand, dispatches generation, manages grid stability.
AEMC (Australian Energy Market Commission): Rule-maker for the National Electricity Market + national gas market. Sets rules covering FiT, retailer conduct, network connection.
AER (Australian Energy Regulator): Sets revenue determinations for DNSPs, regulates wholesale + retail electricity markets, publishes the Default Market Offer + Victorian Default Offer.
DCCEEW (Department of Climate Change, Energy, the Environment and Water): Federal department running the federal Cheaper Home Batteries program + broader energy + climate policy. dcceew.gov.au.
ARENA (Australian Renewable Energy Agency): Federal agency funding renewable energy R&D + demonstration projects. Less directly relevant to residential solar buying, but funds the wider research the industry sits on.

Section 10

Financial + paperwork

IRR (Internal Rate of Return): Annualised return on investment for a solar + battery system over its expected life. Solar IRR typically 15-25%. Battery IRR (post federal rebate) typically 6-12%.
NPV (Net Present Value): Discounted-cashflow value of future savings minus upfront cost. Used by analytical buyers + commercial solar to compare with alternative investments.
Payback period: Years until cumulative savings equal upfront cost. Solar 4-6 years typical. Solar + battery 6-10 years post rebate. Excludes residual value + tariff inflation.
Cooling-off period: Statutory window (usually 10 business days for Approved Solar Retailers under NETCC) where you can cancel the contract without penalty. Use it if anything was unclear at signing.
CES (Compliance and Electrical Safety certificate): Post-install paperwork from the accredited installer certifying the install meets AS/NZS 5033, AS/NZS 4777 + state electrical regulations. Required for STC + warranty claims. Keep it forever.

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The tools every term references

Rebate calculator → Battery payback → System size → CEC accreditation check → Panel tier explainer →

Spotted a missing term or an outdated definition? Email [email protected]. We update this glossary as standards + scheme rules change.