There are a variety of ways in which you can keep your family warm and healthy this winter. Here you will find the different types of clean heating and how they work.
Low Emission Wood Burners
If you have an existing, lawfully-installed wood burner or other enclosed burner (i.e. one with a door), you can replace it with a burner authorised to be installed under Rules 18c and 18d of the Hawke’s Bay Regional Resource Management Plan.
If you plan to install a new or replacement wood burner, it must be an approved Council 'Clean Heat' type, i.e. it must have a heating efficiency of at least 65%, and an emission rating below 1.5g (Napier) and 0.7g (Hastings) of total suspended particulate per kilogram of fuel burned. Select the correct burner size for the area you want to heat.
This list of authorised woodburners from the Ministry for the Environment website have a range of emission ratings from 0.3g/kg up to 1.5g/kg. You can minimise your neighbourhood’s pollution by choosing a woodburner with the lowest emission ratings, by using dry wood, and by using your woodburner correctly.
The Regional Council is planning to establish a ‘Good Wood’ scheme with firewood suppliers who guarantee to only sell dry firewood. This information should be available at some stage in 2009.
Heat Pumps
A heat pump works on the same principle as a refrigerator, but in reverse. The heat pump takes heat from outside and puts it into the room. A heat pump gives between two and three times the heat value of its consumption of electricity. The most common type is a split system type, where the evaporator is mounted outside the house wall, and a condenser is mounted inside on the floor, or wall. Heat pumps provide a dry heat, so there will be no condensation or dampness problems. Heat pumps can also be used for cooling and ventilation in summer. There are many different types available including floor standing and wall mounted heaters. Get advice on the right location in your home, and the best way to operate it to maximise efficiency and lower costs.
Inverter Models
An inverter heat pump detects subtle fluctuations in room temperatures and adjusts automatically, unlike a conventional type which starts and stops repetitively. An inverter heat pump heats up more quickly as well and has an improved heating performance at low outside temperatures. An inverter heat pump is 30% more energy efficient than a conventional type, but generally costs more to buy.
Refrigerants
Most heat pumps have refrigerants that have an ozone depleting potential (ODP), although this potential is significantly lower than the older hydrochloroflorocarbon (HCFC) type of refrigerants. It is possible to specify a zero ODP refrigerant, but this typically adds several hundred dollars to the price of the heat pump.
Controllability
Heat pumps are highly controllable, allowing you to choose the temperature of the room and when you would like the heat during the day. Many heat pumps have additional programmable features. Heat pumps operate quietly and some have an additional ‘sleep’ mode feature that allows very quiet operation.
Running Costs
Since heat pumps are two to three times more efficient to run than radiant or convection electric heaters, their running costs are typically two to three times lower.
Flued Gas LPG Heaters
There is a big difference between a flued gas heater and a mobile or portable gas heater. Mobile gas heaters are commonly used in Hawke’s Bay, but when used they produce a lot of moisture and sometimes gas smells inside the room and it is important to keep the room ventilated and have the heater and gas bottle well-maintained.
Flued gas heaters produce a dry, smell free heat in the room as all the combustion products (water and gases) go out of the flue. You can have these connected to the main gas supply or have gas cylinders installed outside the house which are hired from the gas company who regularly refill them.
It is possible to buy flame-effect fires, both free-standing and in-built models are available, but the most efficient are Energy Saver gas heaters with efficiencies of 85%.
Controllability
An advantage of gas heating is that it can be highly controllable, with options to have both a temperature thermostat and a programmable timer. The thermostat senses the temperature of the room and switches off the heater once a pre-set room temperature has been reached, and the timer allows you to choose the times of the day when you want heating.
Pellet Burner
Pellet burners are a new type of home heating in New Zealand and are favoured by clean air planners because they are relatively 'operator proof'. You buy pellets (that look like the rabbit food variety) made of sawdust - meaning there's no burning of wet wood, and as the fire turns itself on in the morning, there is no smoky overnight bank up.
Though its cost — around $3,300 plus installation — puts it at the top end of the woodburner price list, at under $5 a day to heat the whole house, the operating cost is about the same as older woodburners and it is a lot more effective, with an even heat output all day.
The big benefit is the convenience. The fuel is fed in automatically - you only have to add pellets to the hopper every couple of days. The fire is set to come on automatically (air heated by an electric glow-plug ignites the pellets). The emission rate with the highly efficient combustion of pellets is very low, and it doesn't need a big chimney. It produces very little ash and goes for around two days (burning for up to 15 hours a day) on one bag of pellets. The downside of pellet burners, for some, is that they need electricity to operate. But battery backup can generally be installed. You don't need to collect or buy and store lots of wood, split it, keep it dry in all weathers, bring it into the house with all the attendant dirt and mess - just a dry bag of pellets in a cupboard. And you still can enjoy a cosy flame.
Diesel Heaters
Again these are flued heaters so that the combustion products are extracted from the room. A diesel tank would need to be installed near the house, which can be costly, but again this would be filled on a regular basis by the supply company. These heaters are highly controllable with options to have both a temperature thermostat and a programmable timer.