Designing a sustainable home means balancing two forces that pull in opposite directions in a cold climate like Melbourne: embodied carbon when materials are manufactured versus operational performance, which is how well your home uses and stores thermal energy once built. This BLOG discusses this tension in your choice of flooring and sets out options to assist your decision.
Ask for a maximum power demand assessment for your home if you are planning to change over major gas appliances to electric. Receive a report of your maximum power demand covering: your home’s maximum load capacity, existing and forecast demand, and upgrade recommendations for adding new major appliances with budget estimates.
This BLOG discusses issues and options for ventilating an airtight home. Airtight homes have less natural ventilation coming through gaps and cracks. With windows closed and no mechanical ventilation system in place, you may wind up with an unhealthy home. In fact, it could lead to a dangerous buildup of carbon dioxide, carbon monoxide, mould and mildew.
Consider power for your electric home at the design stage. Removing gas as an energy source will put more load onto your power supply. Therefore, your home must be energy efficient and have energy efficient appliances. Also, this is required by new 7-Star ‘Whole of Home’ building code, for renovations and new buildings.
This BLOG explores options for electric underfloor heating, radiator panels and hydronic convectors. It includes hydronic and electric-resistance systems. It excludes reverse cycle air conditioners, which are a subject of their own and do not radiate heat. Hydronic systems are a lot more expensive to install but a lot cheaper to run and add greater capital value to your home. Electric resistance systems are much cheaper to install but a lot more expensive to run. These systems do not stir up dust, airborne pollen and other allergens. Therefore, they are better for people with breathing issues such as asthma. They can be installed as underfloor radiant systems, radiator panels or fan-coil convectors.
The Galletti ART-U can coil convector provides hydronic cooling and heating with a heat pump. The ART-U convector is designed for cooling in summer using chilled water from a reverse cycle heat pump. An internal fan draws air through its coils. Condensation is drained away outside, which gives you latent cooling as well as sensible temperature cooling. In winter, hot water from the heat pump is circulated through the convector.
This BLOG discusses the causes and suggests steps to improve your house heat loss in winter and heat gain in summer. The causes come broadly from 3 areas, about one third each: (1) ceilings, (2) windows and (3) walls, floors and general air leaks. Your choices on what do depend firstly on whether you are building a new house, renovating an existing house or improving the thermal performance of an existing house.
Replace your gas boiler with a hydronic heat pump for efficient heating and a cooling option using your solar power. Benefits include lower operating costs, less greenhouse emissions, adding value to your home, and safer appliances with longer operating life. However, you should also work on improving the thermal performance of your home. Also, explore upgrading your power supply. This BLOG discusses the key points.
The factors affecting HVAC design should be considered from the outset. Otherwise, it may lead to costly changes through the building process. Therefore, put some time and effort into thinking this through as the first step.
You can enjoy underfloor heating and cooling if you are renovating or building with suspended floors. Use a heat pump as the heat source to have reverse cycle cooling in summer as well. This will absorb heat from your home and expel it outside in reverse cycle mode. You can apply most types of floor coverings over your underfloor heating circuits including tiles timber boards and loose weave carpet.
Great Technology Fusion – Heat pumps, solar power and thermal battery storage are a perfect fusion of technologies:
1) Program your heat pump/s to run during the day with your solar power
2) Store thermal energy in your slab, water and other thermal mass of your home
3) Shift energy release after sundown
Reduce heat loss and running costs, and improve air quality with Heat Recovery Ventilation (HRV). This BLOG explores HRV and ERV ventilation systems. Homes built years ago were not designed for efficiency and so they leaked air everywhere. Modern homes with 6+ Star rating are much more air tight and require ventilation systems to keep a fresh feel inside without needing open windows in winter and summer. Air leaks and open windows can account for a quarter of your energy costs.
Heat pumps use water to transfer heat to your home in winter from the outside air and reverse this process in summer to keep your home cool. Water is 3300 times more capable of transferring heat than air so you don’t need large air ducts with heat pumps.
Consider a home power upgrade if you plan to add new electrical appliances like heat pumps for heating, cooling, hot water, and pool heating, or electric vehicle charger, induction cooktop, etc. This BLOG explores approaches and pricing. Good power supply ensures that all your electrical appliances will run efficiently with longer life.
Heat pump refrigerants have steadily evolved since 1987, when the Montreal Protocol set the objective of phasing out harmful refrigerants for the environment. All heat pump and air conditioning refrigerants have their pros and cons. Due to urgent action needed now to avoid catastrophic climate change, natural and man-made refrigerants with low GWP are becoming essential. This BLOG discusses man-made and natural refrigerants. The latter are gaining widespread support because of their environmental and performance benefits, which outweigh concerns about flammability (apart from CO2) that can be managed.
This all-electric house renovation in Toorak involved going off gas and replacing the old ducted air conditioning system with hydronic heating and cooling. Both form and function of the heating and cooling system were important for this project. New radiator panels, hydronic towel rails and fan-coil convectors were installed, powered by an electric heat pump.
Reduce sound reverberation of hard floors on underfloor hydronic systems. Replacing carpets with hard floors works well with underfloor hydronic systems, but may cause higher levels of sound reverberation. This BLOG discusses this issue and ideas to address it.
Do I need a buffer tank with a hydronic heat pump? Heat pump buffer tanks are recommended for heat pump hydronic systems for three key reasons:
1. Hydraulic separation for hydronic systems with heating and cooling
2. Prevent short cycling with insufficient water volume from room zoning
3. Additional thermal storage of heat produced by heat pumps using daytime solar power.
An energy assessment identifies areas to better manage. It leads to a plan for better energy management that reduces energy costs. Do an energy assessment to help you understand, measure, verify and better manage your energy use. This is more important for a large house or commercial facility, where energy use is higher. If you can measure it, you can manage it!
This BLOG discusses slab insulation so that you can effectively store energy and reduce heat loss from your slab-on-ground. Insulate underneath and also the slab edges. This is very important if you have solar power because you can store excess solar energy in your insulated slab. However, a slab with no insulation creates a thermal bridge for heat to flow outside, draining away your solar energy.
