Multiple Trading Relationships proposal will benefit consumers

The Multiple Trading Relationships Phase One proposal will provide customers with more choice over how they buy and receive fair payment for exported solar. We agree that this will provide a net benefit to all consumers through incentivising efficient investment and operation of customer battery and solar systems that can lower wider system costs. For example, consumers will be able to choose a retailer that provides the lowest grid prices for consumption, and another retailer that provides the best buyback rates for export.  

The changes can also help to improve equity in relation to access to solar systems for renters. It is important that barriers to renters and low income households to access solar and batteries are addressed so all households can unlock significant energy bills savings. This change would lower one of those barriers around choice of retailers. 

Rewiring is working on a Solar for Renters trial, demonstrating solutions to share the benefits of solar between renters and landlords. This MTR proposal would improve choices for landlords under one of the trialled solutions which requires a retailer to facilitate per-kWh volume payments from the tenant to the landlord.  Without MTR landlords and renters would be limited to only picking from the retailers who offer "virtual meter" software service*, which is a very small pool (only Octopus at time of writing). Even if there were other retailers offering better solar buyback rates, they would be limited to just the retailers that offer this service, which means it’s an artificial limit on how the property owner can set up their system, and therefore an artificial limit on the potential return on investment for the landlord (and in turn, the savings that could be offered to the tenant). If the MTR proposal was in place, the landlord would be free to choose any export retailer, separate to the consumption retailer selected from the small pool that can facilitate this particular Solar for Renters option.

*The “virtual meter” software service talks to the solar inverter’s API to measure how much generated electricity is being self-consumed by the property.  This is required so that the landlord can accurately charge the tenant for the power used to get a return on investment (alongside any excess that is exported). The retailer measures the consumption for accurate billing, and may also facilitate the payment between renters and landlords so that it’s all on the same bill.  The volume rate the renter pays for the solar would be below what they would otherwise pay from retail supply so there would be a saving for the renter and benefit paid to the landlord. 

Recognising that different communities have different needs, the MTR proposal has particular relevance for iwi, hapū and whanau Māori seeking to unlock the benefits of local energy generation and sharing. Marae and papakāinga are natural community energy hubs, often hosting larger rooftops and community infrastructure capable of generating surplus solar that could directly support surrounding whānau housing if regulatory barriers were reduced. MTRs are a key enabler of this approach, allowing consumers to more easily share energy and receive fair payment for exported solar while choosing retailers that best meet their needs. This flexibility could support innovative Māori-led energy models, including solar sharing between marae and nearby homes, helping to reduce energy hardship, strengthen resilience, and retain economic value within communities. Examples already exist, such as Māniaroa Marae near Mōkau sharing solar generation with surrounding homes, and the Kia Whitingia project, which installed solar across five marae in Manawatū with energy benefits flowing to local households. Enabling these kinds of arrangements at scale would support Māori economic development, accelerate electrification uptake, and create community-owned infrastructure that delivers long-term social, cultural, environmental, and financial benefits.  

Accelerate additional functionality to allow fairer peer-to-peer trading and energy sharing

We think that the Authority should progress further functionality of MTR as a priority that could help unlock greater value for customers through peer-to-peer trading and community energy sharing.  

We think it is important to ensure customers can share the full value of their solar.  For example, for peer-to-peer trading or solar sharing between customers on the same distribution network – the value of the solar should in theory offset both transmission costs and generation costs.  For customers who are located on the same distribution transformer, we think the net effect on the distribution network is likely to be negligible (i.e. voltage and thermal constraints are uneffected) therefore in this case distribution cost should also be offset.  In practice this could be achieved by shared or traded solar offset the full volume based retail cost (eg: c/kWh charge) on the receiving customer's bill, for neighbours.

Designing a mechanism where retailers can facilitate peer-to-peer trading and energy sharing in this way should be undertaken to deliver greater customer value and not be limited to bespoke platforms which only transfer value based on the export tariff solar owners receive from retailers.

About Rewiring Aotearoa

Rewiring Aotearoa is an independent non-partisan non-profit, funded by New Zealand philanthropy. It is a registered charity working on energy, climate, and electrification research, advocacy, and supporting communities through the energy transition. The team consists of New Zealand energy, policy, and community outreach experts who have demonstrated experience both locally and internationally. We’re always fighting for the New Zealanders who use the energy system, and our goal is to help build a low cost, low emissions, high resilience electrified economy for Aotearoa NZ.

‍

‍