A simple guide for homeowners using Australia’s Cheaper Home Battery Program (CHBP)
Australia’s nationwide Cheaper Home Battery Program (CHBP) sets strict rules around what installers must explain to you in writing before you commit to a home battery system. These rules ensure you’re getting a system tailored to your home—not a generic “20 kWh for $X” package. And here’s the key point:
A quote that focuses only on the battery’s kWh size is NOT CHBP-compliant. In fact, the nameplate size of the battery is one of the least important pieces of information.
Below is a clear guide to what should be included in your CHBP-compliant quotation—and what matters far more than battery size.
What is kWh, MWh, and the difference between size and throughput?
Let’s start with the basics.
- kWh (kilowatt-hours) measures energy capacity—how much energy the battery can store at one time
- MWh (megawatt-hours) is a thousand times larger and is used to measure total lifetime energy throughput
- Battery size refers to the capacity (e.g., 10 kWh)
- Throughput refers to how much energy the battery can deliver over its lifetime — and this is often the MOST important metric
Throughput determines real-world value. A battery with high throughput and low degradation can cycle daily for many years. A battery with low throughput may wear out much sooner, even if its nameplate size looks large on paper.
The right battery size must match your solar system—not a sales target
Installers must explain how the proposed battery size relates to your solar system, including:
- How much excess solar you typically export
- How often the battery will fully charge
- Why that particular size is appropriate for your roof, orientation, and shading
Many installers skip this completely and simply write “X kWh battery recommended.” If the quote doesn’t explain WHY the size was chosen, it is not compliant.
The right inverter size—not just "included"
Your quote must specify:
- The inverter model and size
- Its charge and discharge limits
- How it interacts with both your solar and battery
- Whether it causes solar clipping or limits backup performance
Some installers gloss over this information, but the inverter determines whether the battery can perform at its intended level. If it’s not clear, ask for a written explanation.
Your current and future electricity needs—not assumed
CHBP requires installers to assess:
- Your current electricity usage
- Seasonal patterns
- Future changes such as an EV, heat pump, pool, renovation, or household changes
Some quotes rely on generic assumptions—usually to upsell you a battery larger than you need. Your home isn’t average, and your quote shouldn’t be either.
Whether extra tech is needed for VPP participation
If you want to join a Virtual Power Plant (VPP), your installer must disclose:
- Whether additional hardware or software is required
- Any costs associated with joining now or later
- Compatibility limitations
Some quotes list “VPP-ready” without explaining what that means. If VPP participation matters to you, make sure the pathway is clearly documented.
The most critical information: How the battery is expected to perform over its warranty
The size of a battery matters far less than how it performs every day over its lifespan. CHBP requires your quote to include:
- Expected usable capacity over time
- Degradation expectations
- Total lifetime throughput (in MWh)
- Cycle limits or performance guarantees
Why throughput matters:
- A battery with higher throughput can deliver far more total energy over its life.
- A battery with low throughput may degrade faster or be limited in how many full cycles it can perform.
- Throughput directly affects savings, backup reliability, and system payback.
Think of size as the fuel tank, but throughput as the engine life.
IMPORTANT: Some savings models provided to homeowners assume batteries will deliver 100% of their throughput for 20+ years—even when the battery is only warranted for 10 years. This can inflate projected financial returns.
If savings are calculated assuming the battery runs like new for double its expected lifespan, then the cost of replacing a battery (and potentially the inverter) has not been included. Here’s what you should check:
- Has your installer factored in the cost of replacement when the battery’s performance degrades? Because it will.
- Does the savings estimate assume unrealistic battery performance?
- Have they clearly outlined the manufacturer’s warranty terms, including:
- Minimum guaranteed throughput
- Cycle limits
- Total years covered
- Expected degradation curve
If these details are missing, ask your installer to update the quote.
Why quotes based only on "kWh" are not compliant
Some installers still provide simple “10 kWh battery = $X” quotes. These are not CHBP-compliant and hide essential details about:
- Performance
- Inverter limitations
- Usage assumptions
- System design rationale
- Long-term value
- Expected degradation
- Warranty throughput guarantees
A compliant quote must show WHY that size is right for your home and how the system is expected to perform.
If anything feels vague or generic, ask for clarity
A trusted installer—especially one from the Enphase Installer Network—will walk you through every detail so your system is tailored to your home and built for long-term performance.
The Enphase IQ Battery is Australia’s #1 battery for reliability, safety, and real‑world performance
Click below to request a consultation with an Enphase expert. We’ll call first to understand your needs, then connect you with your local certified installer.
