New Zealand’s electricity market was designed around two kinds of participant: generators that make power, and consumers that use it. A battery does both — and that single fact has quietly been one of the biggest regulatory headaches in the country’s energy transition. In June 2025 the Electricity Authority published a roadmap to fix it. Here is what that roadmap actually changes, and why it matters before you commit to a battery project.

If you are planning a battery energy storage system for a NZ commercial, industrial, or utility project, the regulatory environment is shifting underneath you in a good way. The Electricity Authority Te Mana Hiko has set out a two-year work programme to update the rules so batteries can earn what they are worth. Below is the plain-English version of what is in the roadmap, what has happened, and what is still to come.

Why a roadmap was needed at all

The core problem is older than any battery on the grid. It is written into the legislation itself.

• The legal mismatch: Section 7 of the Electricity Industry Act 2010 defines participants using the traditional categories of “generator” and “consumer”. A BESS is both — it consumes power when charging and generates when discharging — so it does not fit cleanly into either box.
• What that ambiguity caused: uncertainty about how batteries are treated for market participation, dispatch, and compensation. Investors could not confidently model revenue when the rules were not written with their asset in mind.
• Why it matters now: the Authority expects a significant increase in batteries connecting to NZ’s power system as variable wind and solar grow. The rules had to be fixed before that wave arrived, not after.
• The Authority’s framing: the roadmap exists to update the Electricity Industry Participation Code 2010 so batteries integrate efficiently — improving competition and, ultimately, delivering more affordable electricity for consumers.

What the roadmap actually is

The BESS roadmap is not a single rule change. It is a published two-year programme of interlocking workstreams, each addressing a different barrier to battery participation.

• Draft published: June 2025, with feedback invited from industry by 31 July 2025 through the Authority’s Future Security and Resilience team.
• Finalised and updated: the Authority considered all feedback and published the updated roadmap, setting out its BESS work programme for the next two years (through roughly 2027).
• Scope: deliberately focused on BESS specifically — the main type of energy storage likely to connect to NZ’s power system over the next few years.
• The structure: the roadmap diagram (Appendix A of the published paper) maps each workstream against a timeline — what is being consulted on, what is being drafted into Code amendments, and what is already in force.

The first reform already in force (August 2025)

The roadmap is not theoretical — its first stage is already live and changing how batteries participate.

• The date that matters: 7 August 2025, when the first stage of the Authority’s amended procurement plan came into force.
• What it changed: it enabled fuller battery participation in ancillary and reserve services, and clarified how storage is classified during its charge and discharge cycles — improving the market signals batteries respond to.
• The frequency keeping opening: a specific workstream is enabling BESS participation in the multiple-provider frequency keeping market — historically dominated by large hydro. This opens a new revenue stream.
• Why this is the important one for buyers: it directly affects revenue today. The services in our guide to battery grid services became more accessible the day this reform took effect.

The “constrained off” problem the roadmap is fixing next

One of the most consequential issues in the roadmap is technical, but it directly affects whether a battery earns fair compensation.

• What “constrained off” means: when the system operator instructs a generator to reduce output for grid reasons, the wholesale market has rules for compensating that lost generation. Those rules were written for conventional generators.
• The battery problem: the current compensation rules do not properly recognise that batteries are highly controllable assets that respond instantly. A battery constrained off can be under-compensated relative to the value it provides.
• The dual-dispatch challenge: the Authority is also working with the System Operator on the awkward situation where a BESS is dispatched to generate and consume at the same time — a scenario the old market design never anticipated.
• The consultation timeline: the Authority’s review of wholesale arrangements to unlock BESS benefits sought feedback by 23 December 2025, with proposed Code amendments to follow through 2026.

What is still coming through 2026–2027

Several workstreams remain in progress, shaping the environment a battery commissioned in 2026 will operate in for decades.

• Wholesale market optimisation: work to simplify BESS participation and optimise dispatch, potentially unlocking more revenue streams through Code amendments.
• Hybrid systems: the Authority announced upcoming consultation papers (early 2026) on BESS and hybrid configurations — solar-plus-storage and wind-plus-storage at one connection point.
• Distributed and consumer-sited BESS: workstreams examining how smaller batteries — including consumer-owned and EV batteries — can provide services and be fairly paid.
• Participant definition reform: the deeper question of how the Act and Code should categorise an asset that is neither purely generator nor purely consumer.
• Why buyers should track this: each completed workstream typically improves the revenue case. A project marginal under today’s rules may look clearly viable under the rules arriving in 2026–2027.

06What this means for your project decision

The regulatory direction is consistent and favourable, which changes how a buyer should think about timing.

• The trend is one-directional: every reform in the roadmap so far has expanded what batteries can do and improved how they are compensated. None has reduced battery opportunity.
• Revenue stacking gets easier over time: a battery commissioned in 2026 will operate under progressively more favourable rules as the remaining workstreams complete through 2027.
• Chemistry interacts with regulation: the more revenue streams open up, the more cycle life matters. A vanadium flow battery rated for 25,000+ cycles can stack arbitrage, reserves, and frequency keeping without the cell degradation lithium shows under heavy use.
• The honest caveat: regulatory timelines slip. The two-year roadmap is a stated intention, not a guarantee. Model your project on today’s rules and treat future reforms as upside, not as the basis of the business case.

Conclusion

The Electricity Authority’s BESS roadmap is one of the most consequential pieces of energy regulation in New Zealand right now, and it is moving in a direction that consistently favours battery owners. The August 2025 reforms already expanded ancillary services access. The constrained-off and dual-dispatch fixes are working through consultation. The hybrid and participant-definition workstreams will land through 2026 and 2027. For a buyer commissioning a 25-year asset, the takeaway is simple: the rules are getting better, not worse, and the project you scope today will likely operate under a more favourable framework every year of its life.

For a plain-English briefing on how the roadmap affects a specific NZ project, the Zion Technologies team can put together a written summary within 48 hours.