Home / New Zealand guides / Load planning / Watts versus kilowatt-hours: Community building
New Zealand planning guidance for a specific property and load boundary. Use the proposed outage occupancy rather than normal weekly averages. H2OME remains in early development.
Power describes the rate of electricity use; energy describes how much is used over a period. A kilowatt is 1,000 watts. A steady 1 kW load operating for one hour uses 1 kWh. These units answer different questions: whether equipment can support a load now, and how much usable energy a schedule needs.
A storage headline in kWh cannot establish the output power available in kW. Conversely, an output rating cannot establish operating duration. Check whether a quoted energy value is gross stored energy, usable electrical output or a laboratory result under conditions unlike the intended property.
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.
Keep the 0.38 kW assumed base demand beside the 3.04 kWh consumed over the 8-hour base window. For a community building, confusing those two figures could either understate the required store or overstate the supply power needed; neither number describes motor starting.
Use the proposed outage occupancy rather than normal weekly averages. 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, a separate fan at steady input draws an assumed 45 W for 8 hours: (45 ÷ 1,000) × 8 = 0.36 kWh. The combined illustrative demand is 3.4 kWh.
The energy total is modest, but adding it does not change the distinction between output capacity and duration.
For arithmetic only, if the complete storage chain had a hypothetical 30% round-trip efficiency, delivering 3.4 kWh would require 3.4 ÷ 0.30 = 11.3333 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: A separate fan at steady input, 45 W for 8 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. Use the proposed outage occupancy rather than normal weekly averages.
No. The 3.4 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.