Home / New Zealand guides / Charging sources / Off-peak grid charging: Multigenerational home
New Zealand planning guidance for a specific property and load boundary. Reserve energy across different waking hours. H2OME remains in early development.
A night-rate or other time-based electricity plan can create a charging window, but the tariff and the physical supply limit are different constraints. Check the actual plan, meter arrangement, existing overnight demand and available headroom with the retailer and electrical professional.
Cheaper input does not make hydrogen conversion efficient. Compare the total electricity needed to restore usable output, including losses and auxiliary loads, against the practical charging window. Do not claim a saving before actual tariffs, measured efficiency and system costs are known.
Multiple hot-water cylinders, heaters and kitchen appliances need a staggered-use assessment rather than a blanket inclusion.
Different sleeping patterns, separate kitchenettes and mobility needs can extend the essential operating window. A single family representative may miss appliances used in another part of the house.
For a multigenerational home, map the 5.76 kWh base demand onto the actual tariff periods rather than moving the entire 16-hour base window into a night-rate window on paper. The extra four-hour household load competes with replenishment only during its real operating interval.
Reserve energy across different waking hours. Accessibility and medical needs require their own contingency arrangements. An unproven energy system cannot be the sole basis for a care or evacuation decision.
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 multigenerational home, assume the selected base loads average 0.36 kW for 16 hours: 0.36 × 16 = 5.76 kWh. Separately, an extra household load competing with charging draws an assumed 200 W for 4 hours: (200 ÷ 1,000) × 4 = 0.8 kWh. The combined illustrative demand is 6.56 kWh.
This energy remains household demand; it reduces the headroom available for charging.
For arithmetic only, if the complete storage chain had a hypothetical 30% round-trip efficiency, delivering 6.56 kWh would require 6.56 ÷ 0.30 = 21.8667 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: 16 hours. Extra illustrative load: An extra household load competing with charging, 200 W for 4 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.
Different sleeping patterns, separate kitchenettes and mobility needs can extend the essential operating window. A single family representative may miss appliances used in another part of the house. Reserve energy across different waking hours.
No. The 6.56 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.