First things first. Energy efficiency is key. In a recent report from the World Future Council on how San Francisco can reach 100% renewable energy, a full 50% of the means to achieve it came down to energy efficiency. And so it is with your home. The 'Zero Energy Home' in Point Chevalier, Auckland requires no gas or electricity for heating, relying solely on a concrete pad which absorbs heat when the sun is shining, and slowly releasing it again in the evening when it is required. This, combined with good insulation and smart ventilation, means that a heat source simply isn't required. While installing a concrete pad may not be possible unless you're building or renovating, insulation can be installed, and draught-proofing can be carried out. Double glazing can also be retrofitted, the advantages of which include being warmer in winter and cooler in summer, reducing condensation and cutting noise.
Insulation and heating
Before boosting your heating system, carry out energy efficiency measures and you'll find you might need a unit with a smaller heating capacity. When you consider that (electrical) space heating makes up almost a third of the average power bill, it's worth getting the smaller model. In descending order, choose passive solar options, wood or pellet burners, heat pumps or flued gas heaters. Avoid panel heaters, oil-filled column heaters and especially unflued gas heaters.
Solar
It's going to cost you the guts of $7000 - $10,000 to do it right, but solar photo voltaic (PV) panels are going to cut a swath through your power bill. Wait until you've made your home energy efficient and re-measure your power use before choosing what size array you need. Get a slightly larger inverter than your panels need, because in future you may want to add more panels to charge your electric vehicle. Provided you choose the right-sized array for your needs, PV should pay itself off within eight years.
Water heating
Another third of your energy is used for heating your hot water.
Fortunately the days of the traditional hot water cylinder are drawing to a close, as they are being bullied out of existence by their radically more efficient successors. Top of the list are heat pump water heaters, which will immediately slash your water heating bill by up to two thirds and can be installed for as little as $2500.
Solar hot water, effective and efficient while the sun is shining, is nonetheless expensive to install so has a relatively long pay-off time. Gas hot water, whether through storage systems, or 'on demand' systems, come next for efficiency, but rely on fossil fuels.
Looking at replacing the old electric cylinder? Check out these alternative hot-water systems.
Electronics
Electronics take up around 18 per cent of power usage. If you have solar power, charge all your mobile devices during the day. Turn off appliances at night, as left on standby they are just wasted money.
Appliances with the Blue Energy Star mark are among the top ten per cent for efficiency. Refrigeration takes around 11% of the electricity used in your home. Over the 15-year life of a fridge, an efficient model will more than pay for itself.
Lighting
Ever burnt your hand on a bulb? That's wasted energy, converted into heat rather than light. It's also why lighting makes up eight per cent of your energy use. Changing your bulbs to LED models will save 80% of that energy and last for years. Over the life of the bulb, it will save around $110 dollars, dwarfing the initial investment.
Water
Aucklanders use an average of 175 litres of water per person per day, or almost 64,000 litres per year. At $1.34 for 1000 litres of water, that's $85.76.
However we are charged not only for the water which comes onto our properties, but also for the waste water which leaves it. This is charged at $2.28 per 1000 litres, which adds another $146 to bring the total to $231 per person, per year.
An average home in New Zealand has 2.5 people, which brings the water bill to $462 - leaving out the $190 fixed charge, which nothing can be done about. Again, extrapolated over a 25-year mortgage, water charges are likely to be over $11,000, with a further $5000 of fixed charges (and ignoring any future, almost inevitable, rises in water charges).
Quick water tips:
•Install a rainwater collection system, if only for use on your garden
• Re-use dishwater: Pour washing-up water (provided you have used an eco-friendly detergent) over your flower beds - it will help eliminate garden pests
•Install a dual-flush toilet cistern: Also install a low-flow shower head - the best models will save 50% of your water use.
•Repair perished washers: Dripping taps can waste up to 90 litres of water per week.
•Apply good mulch around trees: Up to 73% of garden water evaporates before plants absorb it.
This editorial series is made possible with funding from Energy Alternatives. To find out more about energy efficient products visit energyalternatives.co.nz
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