Home / New Zealand guides / Professional electrical design / Single-phase and three-phase boundaries: Community building
New Zealand planning guidance for a specific property and load boundary. Keep life-safety systems within their own professional design scope. H2OME remains in early development.
The phase arrangement influences which loads can be supported and how demand is distributed. A property may have three-phase machinery alongside single-phase household appliances. Supply type must be established from authorised service information and professional inspection, not guessed from appliance size.
A 10 kW design target does not establish phase capability, phase balancing or compatibility with a three-phase motor. Ask for the actual proposed equipment configuration and tested limitations. Treat large production loads as a separate engineering scope.
Commercial cooking, hot water, audio systems and large events need a separate load and occupancy review.
A hall, meeting house or shared facility can be quiet all week and busy during an outage. The operating envelope must name the intended use, occupancy and authorised coordinator rather than assume public shelter capability.
In a community building, locate the real circuits supporting selected refrigeration through professional assessment. The additional single-phase load cannot be divided across phases merely to make a worksheet fit; each phase and any multiphase equipment need their actual design limits.
Keep life-safety systems within their own professional design scope. Backup electricity does not make a building an approved emergency shelter. Fire systems, safe occupancy, sanitation and civil emergency arrangements remain separate responsibilities.
All numbers below are hypothetical teaching inputs, not measured appliance specifications or product performance. The topic-specific extra load is separate from the base set; omit it if your real inventory already counts it. This worksheet does not include conversion overhead, protection design or a contingency allowance.
For a community building, assume the selected base loads average 0.38 kW for 8 hours: 0.38 × 8 = 3.04 kWh. Separately, an additional single-phase appliance draws an assumed 900 W for 1 hours: (900 ÷ 1,000) × 1 = 0.9 kWh. The combined illustrative demand is 3.94 kWh.
This total cannot be spread across phases by arithmetic unless the physical equipment and circuit design permit it.
For arithmetic only, if the complete storage chain had a hypothetical 30% round-trip efficiency, delivering 3.94 kWh would require 3.94 ÷ 0.30 = 13.1333 kWh of charging input. This is not a measured H2OME efficiency or recovery result. Ongoing demand during charging would add to the required input.
Base operating window: 8 hours. Extra illustrative load: An additional single-phase appliance, 900 W for 1 hours. Replace every input with a measured or professionally established value.
In New Zealand, discuss supply arrangements and connection questions with your electricity retailer and distributor. Ask the local council about relevant siting, building and water-use requirements. Use appropriately qualified electrical and hydrogen professionals, and refer workplace safety questions to WorkSafe guidance. This page does not establish a consent or compliance outcome.
For medically dependent people in New Zealand, register with your electricity retailer, the company that bills you, and keep that registration current. Re-register when switching retailers; ask the retailer how the distributor is informed and what clinical confirmation is needed. Follow the clinician and equipment provider's contingency plan. Registration does not guarantee uninterrupted electricity, and H2OME is not a substitute for that plan.
H2OME is in early development. Its 10 kW output figure is a design target, not a proven specification. There is no confirmed price, certification, commercial availability or guaranteed runtime in this guide.
Hydrogen is an energy store, not free energy. Grid input, wind and micro-hydro are the charging options considered here. Each requires its own supply assessment. Do not install hydrogen equipment, modify fixed wiring, bypass protection or improvise a connection from this guide.
These official resources provide energy, consumer and technical background. They are not endorsements of H2OME, proof of its performance or a substitute for site-specific professional advice.
A hall, meeting house or shared facility can be quiet all week and busy during an outage. The operating envelope must name the intended use, occupancy and authorised coordinator rather than assume public shelter capability. Keep life-safety systems within their own professional design scope.
No. The 3.94 kWh total is an illustrative demand worksheet, not a runtime result. Actual appliance measurements, usable storage output, starting demand, conversion overhead and reserve limits are needed. The 10 kW design target is not demonstrated output capability.
In New Zealand, discuss supply arrangements and connection questions with your electricity retailer and distributor. Ask the local council about relevant siting, building and water-use requirements. Use appropriately qualified electrical and hydrogen professionals, and refer workplace safety questions to WorkSafe guidance. This page does not establish a consent or compliance outcome. Use the worksheet to brief the relevant professionals, not to install, modify or operate hydrogen equipment.
Ask us about H2OME, tell us about your property or register your interest in the proposed system. We are in early development. No payment or purchase commitment; contacting us does not guarantee a pilot installation.