Are Gas Hot Water Systems Environmentally Friendly? A Wellington Homeowner’s Guide

Wellington plumbers install Rinnai Infinity gas hot water system

Hot water is a non-negotiable part of everyday life – from showers and laundry to cooking and cleaning. For many Wellington households, gas hot water systems offer a reliable alternative to traditional electric hot water cylinders.

A number of different energy sources can power them, but natural gas is one of the most popular options, due in part to its efficiency and low cost. This guide explains how gas hot water systems work, their benefits, available options, typical costs, and what to consider before choosing one for your home.

Key Takeaways

  • Gas hot water systems can be environmentally friendly options, particularly continuous flow gas systems in larger households.
  • Gas systems can reduce overall energy use by eliminating storage losses and delivering hot water more efficiently per litre used.
  • In Wellington, gas hot water is generally cheaper to run than traditional electric cylinder systems, offering lower monthly operational costs.
  • Consider household demand and installation requirements to determine if a gas hot water system is right for your home.

 

What Is a Gas Hot Water System?

A gas hot water system uses natural gas or LPG as its energy source to heat water. Unlike traditional electric cylinders that store hot water in a tank, many modern gas systems heat water only when you need it.

When a hot tap is turned on, cold water flows through a heat exchanger that is warmed by a gas burner. The water is then delivered to your taps at a consistent temperature, without relying on stored hot water.

Gas hot water systems are commonly used in New Zealand homes where a gas supply is available and are particularly popular in households with higher hot water demand.

Types of Gas Hot Water Systems

In New Zealand, gas hot water systems can be environmentally friendly, but only in the right context. New Zealand’s electricity grid is largely powered by renewable energy, which means electric hot water systems can have a relatively low carbon footprint. However, gas hot water systems are best assessed on overall efficiency and emissions per litre of hot water produced, rather than fuel type alone.

Continuous Flow (Instantaneous) Gas Systems

Continuous flow systems heat water on demand, meaning there is no storage tank. This eliminates heat loss from storing hot water and reduces unnecessary energy use. These systems are ideal for families, larger households, or homes with multiple bathrooms.

Key benefits:

  • Endless hot water supply
  • Higher energy efficiency
  • Compact design
  • Reduced heat loss compared to storage tanks

 

Storage Gas Hot Water Systems

Storage systems heat water in a tank and keep it ready for use. Storage gas systems are now less common in urban NZ homes but may suit certain properties or usage patterns.

Key considerations:

  • Lower upfront cost in some cases
  • Limited hot water supply based on tank size
  • Heat loss as stored water cools over time

 

Benefits of Gas Hot Water Systems

While gas systems often have higher upfront installation costs than electric systems, many homeowners find the long-term benefits and system lifespan offset the initial investment.

Energy Efficiency

Gas hot water systems are generally more efficient than standard electric systems, particularly continuous flow models. Heating water only when required reduces wasted energy and improves overall performance.

Reliable Hot Water

Gas supply is consistent and not affected by peak electricity demand. Many gas systems also continue operating during power outages, which is a major advantage for Wellington homes.

Endless Hot Water

With a continuous flow system, running out of hot water is no longer an issue—making them ideal for busy households.

Long System Lifespan

Gas hot water systems typically last longer than electric cylinders when properly installed and maintained, reducing replacement frequency over time.

Lower Running Costs (in many cases)

Depending on household usage and local energy pricing, gas can be more cost-effective than electricity for water heating.

Lower Emissions Than Some Alternatives

Natural gas burns more cleanly than many fossil fuels and can result in lower emissions compared with some electric systems, depending on how electricity is generated.

How Much Does a Gas Hot Water System Cost?

The cost of a gas hot water system in Wellington varies depending on:

  • System size and flow capacity
  • Brand and efficiency rating
  • Installation complexity
  • Whether gas supply upgrades are required

 
For accurate pricing, a professional assessment is always recommended.

Popular Gas Hot Water Brands in Wellington

Several reputable manufacturers supply gas hot water systems suitable for NZ conditions.

  • Rinnai – Widely used across New Zealand, particularly known for the Infinity continuous flow range
  • Rheem – Offers both gas and electric hot water systems with a strong reputation for durability

 
A licensed gas fitter can recommend the most suitable model based on flow rate, household demand, and installation requirements.

What to Consider Before Choosing a Gas Hot Water System

The right choice depends several factors, like your household size, hot water usage patterns, and whether a gas connection is available.

Gas Type

Natural gas burns more cleanly and is generally the lower-emission option. LPG produces higher emissions per unit of energy and is less environmentally favourable than natural gas, though still efficient in continuous flow systems. Natural gas is typically preferred where available, but LPG is an alternative for homes without a main gas connection.

Household Size and Demand

Larger households require higher flow-rate systems to ensure consistent water pressure and temperature.

System Efficiency

Look for systems with high efficiency ratings to reduce energy use and operating costs.

Installation Location

Outdoor installations are common and can improve ventilation and efficiency.

Maintenance

Regular servicing ensures safe operation, optimal performance, and system longevity.

Is a Gas Hot Water System Right for Your Home?

A gas hot water system may be a good choice if:

  • Your household uses large amounts of hot water
  • You want an endless hot water supply
  • You have access to natural gas or LPG
  • You value long-term efficiency and reliability

 
Homes without a gas connection or with very low hot water demand may find electric systems more suitable.

Professional Gas Hot Water Installation in Wellington

Choosing the right system is only part of the process. Correct installation by a licensed professional ensures safety, compliance, and optimal performance.

Paramount Plumbing and Gas specialises in gas hot water systems, including continuous flow and storage solutions. Their team can assess your household’s needs, recommend an appropriate system, and ensure it is installed to New Zealand standards.

 

Get In Touch

For any enquiries please phone or email us at: