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Progress and Some Waffle about Electricity

Posted: 13-04-10

Painting fretwork, lining-on, skirting on, doors on. Micro-Gen.

So we knocked-up a to-do list the other day, just like we did for the Brooklyn house. Now a 10 item list don't sound too long until you realise each item might take 2 people several days to complete! The real crux though is this: We need to get our share of the work done - on time - so the house can be valued, the valuation passed to the bank and the funds released to pay our final installment to the builder. But that final installment can only be paid once code-compliance has been issued by, presumably, Kapiti Coast District Council.

Code-compliance (That the home is compliant with the NZ building code funnily enough) can only be issued if the home is weather tight and that wet areas like bathrooms, laundries and kitchens are plumbed-in and impervious to water ingress. The water tightness "clause" stretches to ensuring that weatherboard, windows and doors are all completely protected from the elements with the right paint and sealant products used. As you'll know from reading the blog in recent weeks, I may well have it on good authority that we're saving around $15-$20,000 doing the prep and painting work ourselves, but similarly to those self-managed builds on the UK show Grand Designs, we also have full-time jobs (and to a lesser extend - lives) to carry on with as well, and yet deadlines loom large.

I may well take to fudging the To-Do list you know, just like we did last year and break down each item into sub-items so they get checked-off more frequently. It makes it look as though you've got through more stuff than you really have...

So in the vain of the DIY'ers that we are, we took home all our pre-cut fretwork, modillions/corbals, finials and latticework that will eventually adorn our home so they can be primed and painted in the garage. This makes for a lot of work after coming home from work, cooking and cleaning-up and other chores, but makes for easier work than having to get up a 10m ladder and painting the buggers up there instead.

We've been on-site a couple of times in the last week and I'm due to be up there again for 2-days of leave from work starting Wednesday. All the wool insulation is installed, all the GIB lining is on, and they've started installing all the colonial style skirting and architraves.

I was weighing-up the "Eco" features of our house the other day while idly watching a Grand Designs episode of, well, grand proportions (Solar PV powered, self-heating triple-glazing from Belgium - bloody amazing!) and while in comparison, ours is a fairly crude, stick-framed, timber clad building, its "Eco" credentials, designed-in by us at the outset deserve more than a passing mention I reckon.

The home has or soon will have:

Solar Thermal hot water heating, boosted by a reconditioned 16kW equivalent Rayburn solid fuel cooker. The cooker also provides hot water enough for 2 towel rails and 6 reclaimed 4-column cast-iron radiators.

The weatherboard is a true timber product made from FSC approved NZ Pine. The skirtings and architrave are sourced from the same company - Southern Pine Products who have radically revamped their manufacturing methods to recapture waste materials and heat wherever possible in their manufacturing processes.

Insulation is 100% wool, rated above that the building code requires. We have R2.5 for walls and R3.6 for the ceiling. The stuff we sourced was supplied by Latitude Insulation, we used wool as opposed to glass fibre or even a wool/polyester blend simply because it was a completely natural product and is safe and easy to handle.

The house itself has all the main living areas pointed due north for maximum solar gain during the day. All the windows and doors are of timber joinery for its look and thermal properties, as opposed to aluminium that so many NZ home-owners have had foisted upon them by narrow-thinking builders.

We specified the use of untreated timber for the internal framing of the house, as the most common treatment process known as LOSP uses some hazardous chemicals to preserve it. But if no moisture is allowed in the building there is little chance of rot and therefore no need to be exposed to the continuous off-gassing of this timber preservative. There is of course the issue of the borer beetle though..

The glazing itself comprises 20mm argon filled double-glazed units apart from the front-door.

Water comes from the sky, into 2, 30,000 litre plastic tanks and is filtered by a mains-power-free, membrane filter from Rainline Products. We swapped from the more conventional UV filter due to the sheer amount of power consumed by the latter.

Our wastewater from poos and wees (Known as blackwater) goes into a sub-surface stepper tank behind the house and once settled, the liquid material is periodically pumped to a local wastewater treatment plant, not a municipal one. The farmers who subdivided their farm in 2003 wanted the individual sections and their owners to respect the environs somewhat and part of this is the proper disposal of waste.

We also got the house plumbed-in so that waste water from sinks, bath and showers (known as greywater) would all be channelled to a single gully-trap instead of multiple traps as per normal. This meant more pipe and more money, but it also means we are able to easily install a greywater recycling system such as Watersmart's "Water Lillee" and hook into this main gulley. This simple yet ingenious device cleanses waste water and distributes it via sub-soil hoses to specific zones you control from a wall mounted LCD controller. Zones such as the veggie-patch or areas of trees for example.

We are also due a new fridge/freezer and have selected the 6 star energy-rated KF-320 model from the Swedish company GRAM. This model has 70L greater storage capacity than our current model, and yet it uses half the energy. This becomes all the more important when it comes to finally generating our own power.

We plan to slowly build up our micro electricity generation (Micro-gen for short) capacity for a Grid-Tie setup as its expensive kit and I still have much to learn. Fortunately, our new neighbour is a sparky and is also keen to setup some micro-gen capacity of his own so a knowledge-share is on the cards I'm sure.

Basically, Grid-Tie means you are tied to the grid, but are able to generate as little or as much electricity as you wish and any excess can be sold back to the grid. A fairly major caveat here is that at the time of writing there is no legislation that puts a standard level on what power companies should pay you for your excess power - known as a Feed In Tariff or "FIT". There are moves toward getting this sorted over here with organisations like REFIT-NZ lobbying the government for change on this score to bring NZ in-line with Australia, Germany and recently I believe the UK, who all have legislated for FITs.

As I currently understand it, to be grid-tied means you only need a fraction of the battery storage capacity you would otherwise require if you were completely off-grid. You are either consuming all your power at home, or exporting some of it to the grid. However, until recently you wouldn't have been able to setup in a Grid-Tie system at all because there were no certified systems available to safely isolate your generation capacity from the overhead lines that might be being fixed during a fault. Fortunately there are inverters available now that will do the normal work of an inverter (Converting your DC power from Solar PV or Wind turbine into AC usable by your household) and are certified able to isolate your home from the grid and redirect any generation to a small store of deep-cycle batteries. So depending on how remote you live and the likely hood of being days from being reconnected, this will affect the number of batteries you will buy and of course in any off-grid/grid-tie solution, the types of household appliances you choose to purchase and use.

Now I have been asked why on earth should I want to buy all the kit at such an expense, with little or no chance of payback for at least 30 years. The answer is both as simple or as complex as the asker chooses to make it but the facts are these: Electricity prices are likely only to increase. NZ is renowned for its shaky power lines and substations by the long-skinny shape of the country which doesn't fit well with using multiple tracts of overhead power lines like you get in larger countries, it just has the one. As well as a severe lack of investment in equipment at places the Haywards Substation in Lower Hutt which lies at one end of the Inter-Island HVDC link.

But basically: Energy security = piece of mind. And if I learn something about electricity generation and consumption in the process then it can be called a hobby too.