Posts Tagged: energy

Sustainable lifestyles — No Comments
7
Jan 10

Your place, unplugged

February, 2008

There’s something very James Bond about the idea of having a home which generates all its own electricity. But is it realistic to dream of making the switch to renewable energy?

Too many discussions about the potential for alternative energy are hobbled by a false assumption. The energy we “need” is not the amount of power we are roaring through at the moment. If it were alternative energy would always fail hopelessly to keep up with our insatiable demand. But then so, eventually, would almost every other resource on the planet.

Let’s get things into perspective. The average New Zealand home currently consumes about 8,000 kWh of electricity per year, which is priced at about $1,600 from the conventional grid. This, however, is not the true cost. The real cost of creating this power – about a third of which comes from fossil fuels – in terms of the damage done to our local and global environment, doesn’t show up on our bills.

In choosing to generate our own electricity through environmentally friendly means, we are also aiming to accept the real costs of and responsibility for our consumption. So the first thing to do is to conduct a rigorous audit of the energy use in our home and reduce it as far as possible. Everyone should do this anyway, whether we intend to generate our own or not. You know the drill: energy efficient lighting and appliances, switch things off, keep the fridge closed, full washing machines on low temperatures, insulation…

Energy reduction measures will almost always generate greater economic and environmental savings, per dollar invested, than installing wind turbines and solar panels. So we need to fully explore designing-in energy saving features like solar water heating to a purpose built home or retrofitting them, before investing in generation. It’s not efficient to generate your own power just to cook your dinner and warm your house, so a wood burning stove and/or LPG cooker should be used instead.

The cost of any generation system you may decide to build will largely depend on how much power you need at peak times. A comprehensive energy efficiency drive has the potential to lower our electricity requirements to about 35% or less of that in an average home. Only once we have all this sorted, and ingrained into family life, should we consider generating our own power.

To design a system for your home, you will need to talk to an expert who can help you calculate your energy needs and the energy resources of your site accurately. For urban homes in New Zealand, this will probably mean considering the installation of photovoltaic (PV) solar panels, which convert sunlight into electricity. For those with more space around them, wind turbines and micro-hydro generation may also come into the equation.

You will need to consider local geography, weather and the suitability of your building and its location. In New Zealand PV panels should ideally be placed at unshaded north-facing locations. Wind turbines require a minimum annual mean wind speed of more than four metres per second. This needs to be fairly consistent, since they will not generate in extremely high or low wind at all. To install a micro-hydro unit, you will need your own consistently flowing stream or spring. The system will also need to be backed up with batteries if it isn’t plugged into the grid.

Check the rules and regulations. There are instances where new buildings must be wired into the mains as a condition of their consent. PV panels will usually not require consent, but some wind turbines produce noise and all of them should be at least 10m high. This means they must be carefully sited and require resource and building consent. Micro-hydro systems require a building consent and a resource consent. To avoid damage or risk of fire, appropriate New Zealand standards and regulations need to be observed, including those relating to the installation of batteries and wiring.

Forget any ideas you may cherish about ‘free’ energy; these systems cost money to install and maintain. The sort of generating system, whether PV, wind or a combination of the two, which is likely to make an energy efficient home in New Zealand completely self sufficient will cost between  $35,000-$45,000 to install. At the moment it is highly unlikely this sort of system will pay for itself during its 30 year life expectancy, during which time there will be other costs from wear and tear and battery maintenance.

But there are situations in which it can be highly cost effective. If you are putting a new building up in a remote area, you might be saving yourself the cost of grid connection in the first place, which can be between $18,000 and $24,000 per kilometre. And if you are still connected to the grid, it may be possible to sell electricity back to the power retailer, but they will usually pay less than they sell electricity for. You will need to do a deal with them and comply with the safety and technical requirements of whoever owns the lines to your property.

In economic terms you are balancing the cost of installing and maintain your system, against the present and future cost of grid power. With the energy industry the way it is, this is tough call. In the end it all comes down to how much you are willing to invest in the future of the Earth’s atmosphere, a cleaner conscience, and for the chance to be a lifestyle pioneer.

Sustainable lifestyles — No Comments
7
Jan 10

How green is your garden?

July, 2007

If you find your garden is more about battling with nature than harmony with it, why not try some of these environmentally friendly ideas?

Don’t just grow grass – grow food! Fill a handy tub or two with a kitchen herb garden to add a fresh touch to the air and to your cooking. A few home grown organic veggies can be a real source of satisfaction, and not just for the stomach. It cuts down on the fossil fuels used to get your dinner to your plate and can be a healthy educational pastime for the kids.

Go native! Growing native plants helps bring back New Zealand’s natural treasures. Because these plants evolved to deal with local conditions, they generally require less pest control, fertiliser and watering. Whether it’s the iconic kowhais, pohutukawas, kauris, or lesser known species, check out what you have the space and conditions for.

Store your own rain clouds. Plants don’t need grade-A drinking water. They do just fine with rain from the roof or the remains of your bath. These are also fine for washing your car. Covered tanks and water butts reduce demand on local supply systems which are expensive and put pressure on the environment. To avoid wastage, don’t use sprinklers. Soak the base of plants early in the day or in the evening when things are cool.

If you can’t be bothered to dig, don’t bother! Organic no dig gardens are a great solution on heavy clay or very poor, silty soils. Clear a sunny spot, build a 1.2m wide sturdy box about 40-45cm high from rot resistant timber, brick or concrete blocks. Add several thick layers of old newspaper to the bottom. Add a layer of clean, weed free straw up to about one third of the height of the box. Fill the rest with a mixture of good weed-free soil and high quality compost. With small openings for your seeds, and a little care and attention you should get healthy plants, with no weeds, no sweat.

Waste not want not. Load a 3ft by 3ft heap or bin with a balanced mixture of ‘brown’ carbon rich material, like dried leaves, straw, and wood chips, and ‘green’ nitrogen materials like fresh grass clippings and kitchen scraps. Properly managed, it becomes soil improver in a month. Leave gaps in your stack or turn it, and keep it moist and warm.[i] For health, hygiene, and ease you shouldn’t compost meat, fish, dairy products, oils, pet waste, coal or coke ash, disposable nappies or this magazine (surely you would keep it forever?)

Avoid using peat. Another advantage of making your own compost you can be absolutely sure it’s not being dredged out of valuable wildlife areas, unlike certain soil improvers we could mention…

Put your worms to work. Wormeries use less space than compost, get rid of kitchen scraps faster, and give your kids something to scare their friends with. You need a container about one square foot for every pound of waste, with drainage holes drilled in the bottom. Fill two thirds with well-soaked shredded cardboard or paper. Add a pound of redworms (Eisenia foetida) for every half pound of waste, load your container up slowly, and keep it moist and warm.

Live and let live. Careful planting, physical barriers, organic pesticides and night time slug-spearing removes the need for chemical pesticides which may harm your health, the environment, and the birds and insects which help control garden pests. You need to be vigilant, get in early and keep a tidy garden to be successful. But you can also get ahead by selecting non-genetically modified disease resistant plants from the outset.

Turn off the gas guzzlers. Do you really need all those noisy power tools coughing pollutants into your fresh air? Less lawn means less mowing. What doesn’t grow vegetables can become orchard, or beautiful wildflower pasture. If you really love a little lawn, consider cutting it with an electric or manual push mower.

Get rid of the patio heater, or remove the gas canister and turn it into a bird feeder. The great irony is that their seemingly futile mission, to heat up the entire outside world, may actually succeed if enough of us keep using them. But the devastating effects of climate change would make this cold comfort indeed. Put a jumper on. It’s not cool to be hot at the rest of the world’s expense.

Solar lighting is now a familiar sight in Kiwi gardens. Spending a little more on units that will last ensures the environmental benefits are not cancelled out with frequent replacement.

Go visiting! Gain inspiration and ideas by visiting open gardens, garden centres and organic centres near you. Many of them have wildlife walks and cafes so you can make a day of it. Or join up with friends and neighbours who are green gardening and swap growing tips, recipes and food to form a real link between your community and your land.

Make it fun. Spending time in the garden is such a great low energy using pastime. Make sure your landscaping and design includes plenty of nooks and crannies for the family to get away from it all.

Sustainable lifestyles — No Comments
7
Jan 10

Home, green home

May, 2008

In a recent online poll of 100 people, 10 of them said they would be prepared to pay up to 25% more for a ‘green’ home. But what should buyers of green or eco-friendly homes be looking for?

Green homes minimise their impact on the environment in their location, design, materials, construction and use. They should be beautiful, healthy places to live in, which are long lasting, cheap to run and easy to maintain. Moving home takes energy, disrupts communities and makes it difficult to establish environmentally friendly landscapes and gardens, so ideally you will be looking for somewhere to nest for the foreseeable future.

Eco-luxury is more than skin deep. Oceanic scale spa baths, jet-washing power showers, lawns like Mount Eden Park, television screens which should come with their own usherette, triple garages, lofty entrance halls and chandeliers will pretty soon seem as dated as the episodes of Dynasty which made us want them in the first place. As an eco-house buyer you will be looking past the gadgets, gizmos and status symbols for the true luxury of a well designed home that works beautifully and efficiently.

The assessment starts on the drive in. These days it’s not so impressive for your home to dominate the surroundings like a medieval monarch. You are looking for a home that’s carefully sited to take into account the wind direction, sheltered areas and water flows. This will make living in and around it as pleasant as possible. Also, environmentally speaking, there’s no point buying a super-efficient eco-retreat on the side of a mountain if you have to drive your gas guzzler for two hours to get to work or buy groceries. So check out the local facilities when popping in and out of the estate agents.

What about the neighbours? New Zealand is still blessed with more green open spaces than most westernised nations. But this won’t last if everybody wants a quarter-acre or more with a detached home in the middle of it. Shared walls reduce the energy needed to heat your new home. Shared gardens, preferably vegetable growing, save resources and help generate a positive community atmosphere.  Failing that, are the people over the fence of a similar mind, or will they blight your organic veggie patch with sprays on the boundary, overshadow your orchard with pines and complain about the chickens?

Is this investment insulated? Cold, damp, leaky homes are not good for the environment, outside or inside. Although some green homes are designed to ‘breathe’, this should not be through leaky roofs, doors or windows. Hot water tanks and pipes should also be properly insulated to avoid wasting energy. Bring your torch and check.

Be a sun seeker. Look out for north facing windows which capture the days’ free energy. Combined with exposed dark coloured concrete, rammed earth or adobe flooring, they can create a highly efficient ‘passive solar’ air conditioning system – especially effective if the home is partially buried. The sunny areas are also great greenhouses for food plants and flowers. But check the window design, includes adequate shading, otherwise you could spend summer feeling like an ant under a magnifying glass.

Solar water heating is one readily available green option which can heat between half and three-quarters of your hot water in the right conditions. But check it has building consent and how long it has been there – they only have a life expectancy of about 20 years. There also needs to be sufficient alternative means of heating water and yourself to make up the shortfall in winter. Your ideal may be a super-efficient wood burner with wet back and a local sustainable wood supply, but see what’s there and what could be changed. And keep in mind, the bigger the space, the more energy it takes to heat it.

Solar power generation may look super-green but is still on the borderline in terms of saving money. You can think of it as paying your power bills up front and investing in a brighter future for the planet. Similarly wind turbines offer great green cred, but the power they generate can be marginal unless carefully sited and there is the possibility of damage to the building if they are attached to it. These may also need resource and/or planning consent. Again, check the paper work.

Rammed earth, straw bale, recycled building materials, adobe, cordwood, logs and timber frames are all in use by New Zealand’s more adventurous home builders, and some create fantastic living environments. But before purchasing someone else’s experiment, find the builder and have an expert quiz them thoroughly on its construction and on any problems they had. Remember that as much as you may love their individualistic vision, you will have to maintain it and may have to sell it again sometime.

Keeping rain out is obviously vital, but green homes also store it for use, at the very least for the garden. Keep an eye out for rainwater storage tanks (they may be under the floor), and/or a system for using recycled or ‘grey water’ for the garden or for flushing the toilet. These can add value, but grey water systems particularly need to be checked and preferably tested to ensure they are hygienic and working properly. Anything looking ‘home made’ should be checked by an expert and its paperwork seen.

Sustainable lifestyles — No Comments
7
Jan 10

Home is where the hearth is

March, 2007

The age of fire has not sputtered out in New Zealand. But new rules and regulations mean you have to plan carefully to realize your wood-burning dreams. Kiwi homes have been under pressure to quit smoking since 1 September 2005, when new national design standards for wood burners came into force. As part of the Government’s National Environmental Standards for Air Quality, the latest rules aim to reduce the pollution being pumped out by our domestic fires.

Today’s wood burner has to be a lean, clean, heating machine. All wood burners installed after that date, on properties less than two hectares, must chuck out less than 1.5 grams of particles for each kilogram of dry wood burnt, or one gram if you are in the Canterbury region. They must also have a thermal efficiency of at least 65 per cent. This means more than two thirds of their fuel must be completely converted into heat.

Local council’s are all fired up about pollution. They will require you to obtain consent to install a burner, and it’s important to check with them if they have other criteria which need to be met. In urban Christchurch, for example, you will only get consent for a wood burner if the place had solid fuel heating before.

What’s the fuss? Every marshmallow toasting opportunity generates carbon dioxide and potentially toxic carbon monoxide – two of the gases on the climate change Most Wanted list. An inefficient fire can also contaminate your home and its surroundings with fine particles of soot, hydrocarbons, formaldehyde and other nasties. These risk human health if inhaled over long periods and could pose a cancer risk.

The rules are a breath of fresh air for Christchurch. About 80 per cent of winter air pollution there comes from open fires and wood or coal burners. On some still days the result is skies in a rather retching shade of smog brown. Nelson and Otago have also found themselves under an artificial cloud.

Are the days of the open fire numbered? Old fashioned open fires throw 80-85 per cent of their heat straight out passed Santa’s welcome mat. They are much less efficient and more polluting than enclosed burners and can leave a draft when unlit. Not to mention the possibility of a flying spark burning your des res to the ground while you are rummaging around in another room, looking for some warmer clothes to put on.

Still want a fire with no door? Open fires are not covered by the national standards. But their installation and use, as well as the installation and use of all solid wood burners on larger property, is subject to the regional plan for the area in which you live. Auckland has set an emission limit of less than 4g/kg for those falling under its jurisdiction. Canterbury’s regional plan has already stopped the use of open fires in its Clean Air Zone 1 around central Christchurch, and will also ban the use of wood burners there which are more than 15 years old in 2008.

You can keep the home fires burning. The Ministry of Environment keeps an online list of wood burner models which meet the national standards (see below). It doesn’t cover everything, and the ministry doesn’t guarantee burners from the list will always pass all regulations if tested. But it is in the process of being independently verified and it’s the safest place to start shopping. Fire dealers too, should be aware of the regulations and will offer information and advice. The approved list currently includes 13 manufacturers and more than 70 models, which should be enough to suit anything from a West Coast batch to a Clevedon mansion.

Fire can be cool. Metro’s Eco Tiny Trad is the most efficient on the list, with just 0.72g/kg emissions and 78 per cent of its fuel converted into 9.5kW of toasty glow. It boasts the smallest floor protector of any New Zealand-made wood fire, and is ideally suited for heating areas up to 100 square metres. It can be bought for about $1,200 and installed for under $2,500, so it should keep a small room nice and cozy without burning a hole in your pocket. The imposing Firenzo’s Lady Kitchener EF will pump out about 23kW when fully loaded, enough to warm 200 square meters, and lighten you bank account by about $4,000 including installation.

You get out what you put in. The Ministry’s list states the authorized fuel as dry wood. It recommends only seasoned unpainted and untreated wood with a moisture content of less than 25 per cent. Reading this now, you should have a full stock of firewood in store from the summer, when prices are cheaper. This also allows enough time for it to be loosely stacked under cover to dry out properly. Chop it up yourself if you want it to warm you twice.