Transpower's draft 2026 Security of Supply Assessment warns of a potential energy security gap by 2031 unless the record 1,100 MW commissioning pipeline of generation, batteries and upgrades is accelerated into the 2030s. PowerHub's $149 monthly EcoWave battery subscription offers households a private-sector way to capture low wholesale prices while buffering spikes, providing a market test of whether battery-as-a-service can finally de-risk wholesale exposure after Flick Electric's 2017 failure.

The security warning that sets the stage

Transpower released its draft 2026 Security of Supply Assessment on 23 April. The assessment concludes that system resource adequacy remains adequate but fragile in the short term. It flags a potential breach of security standards by 2031 if investment slows.

CEO James Kilty stated that accelerated delivery of new generation and battery storage must continue into the 2030s. This comes as domestic gas supplies decline and demand is projected to rise 65 percent by 2050.

PowerHub enters this environment with a model that pairs wholesale price exposure plus a 10 percent margin with battery storage. The company seeks $650,000 via PledgeMe to launch, with over $147,687 pledged as of mid-May 2026.

Transpower's NIGU high-voltage transmission corridor near Te Kauwhata, Waikato — part of the national grid that the draft 2026 Security of Supply Assessment warns faces an adequacy gap by 2031 without accelerated investment.

The drivers behind rising household costs

Average residential electricity tariffs reached 39.3 cents per kWh in April 2026. Wellington households paid the lowest at 34.61 cents while Balclutha paid 48.93 cents. Retail prices rose 12 percent in 2025 and face at least another 5 percent increase in 2026.

Lines charges from Transpower and distribution companies account for one-half to two-thirds of typical bills. These regulated costs fund infrastructure upgrades and higher interest expenses. Gentailers control over 80 percent of generation and retail, limiting competition.

Wholesale prices are forecast to fall 31.8 percent to $151.4 per MWh in 2025-26. Yet households miss these savings under fixed tariffs that embed an insurance premium for volatility.

NZ average residential electricity tariff vs wholesale price forecast
Retail tariff is the April 2026 national average; wholesale forecast is IBISWorld 2025-26 projection. The gap illustrates the margin households currently pay over spot rates.
Source: MoneyHub (MBIE QSDEP); IBISWorld NZ Electricity Wholesale Price report