Our new off-grid solar goes in

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One of the things we liked about our farm when we bought it was that it was truly off-grid. That means managing our own power, water and sewage. Truly living the eco dream!

What we weren’t so excited about was the terrible state of the solar generation system. It hadn’t been serviced in the last decade, meaning the lead-acid batteries had been allowed to go dry, the generator was failing, and the lights dimmed every time the water pump when on.

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The old batteries, hugely heavy (50kg+), which had been allowed to go dry

So a brand new PV system was required. Our immediate challenge was finding someone who could sell and install a solar solution.

Our farm is located in a rural setting surrounded by rainforest and fields. But it’s also just 10 minutes away from the nearest town, making it semi-urban.

The net effect is that very few of the local PV systems are off-grid, and few of the local installers had experience with off-grid setups. We wanted someone nearby to do the work, so we could get good post-installation support.

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Installing the new panels on the roof

It’s worth  highlighting at this point that there are power lines that run across a corner of our property. Connecting to the grid, however, would cost $20-30k, and then we’d have to pay electricity bills.

We ended up getting one good quote for a new system, for a total cost of $30k. So the same up-front cost, but with a lifetime of free power. That was an easy decision.

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The heart of the new system, a Sunny Island controller, and a Sunny Boy inverter

The key components of the system are as follows:

  • SMA 6Kw Sunny Island, which is a beautiful bit of kit that charges the battery and manages the local grid
  • 5Kw of solar panels, on the north-facing roof of the house
  • Sunny Boy inverter for the panels
  • 17Kwh of battery storage, utilising lead-carbon gel batteries
  • 7Kw Honda petrol generator, with auto-start
  • web-based interface for monitoring the system

It took the team three days to strip out the old system and to install the new one. Right from the beginning it’s been working well, and getting enough sun even in mid-winter (where the sun hits the panels at 11am, until 3pm when the sun dips behind the mountain).

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The new lead-carbon batteries, quite a difference from the old monster batteries!

A few notes:

  • The general rule of thumb for off-grid is to have 3 days of usage in the batteries, to cover off the occasional rainy week.
  • The generator has been configured to kick in if the batteries reach 30% of capacity, and to then take them back up to 70%.
  • We didn’t use lithium-ion batteries (like the Tesla Powerwall) because they’re not yet designed for off-grid, and the price is still too high.
  • The system operates as a “local grid”, allowing me to re-install the old PV panels on the new shed, connect them to a small inverter, and then just to wire that into the grid. T’he Sunny Island then manages the load across the system as a whole, which is a very elegant solution.

It’s early days for our solar setup, and we’ll report back as the months unfold.

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The new panels in place, three rows for a total of 5Kw

 

 

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Home-made wax fire lighters

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When browsing Pinterest I came across instructions on how to create home-made wax fire lighters.

With a fair bit of unprocessed wax on hand at the end of the beekeeping season, I was very interested. Particularly for the wood fire down at the farm, in these colder winter months.

I started by melting down a big lump of wax, which you can see contains a fair bit of gunk.

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The messy pile of left-over wax at the end of the beekeeping season

A good friend of ours provides us with big bags of free wood shavings, to use in the chicken coop. I used these to fill up a number of paper muffin cups.

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Muffin cups filled with wood shavings

The hot wax then went into the paper cups, the result being (once cooled), a set of unusual-looking fire lighters.

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One of the final products — and it works!

Now I won’t claim that these are as quick and easy as the fire lighting blocks that you can buy. They take a bit of convincing to light, but once they’re going they work well.

They’re particularly effective at restarting the fire each morning, as the coals are still warm from the night before. This primes the wax to light more easily.

If nothing else, these are a great way to make use of available materials that we get for free, namely: wax and wood shavings. Happy days.

First step towards an edible forest garden

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As blogged about previously, our long-term goal for our South Coast property is to create an “edible forest garden“, following the books by Dave Jacke.

This week we took the first steps towards this big vision, with the planting of our first fruit trees.

The trees were all transplanted from Lewisham, with the bulk being citrus trees:

  • Ruby grapefruit (dwarf)
  • Cumquat x 2 (dwarf)
  • Meyer lemon x 2 (dwarf)
  • Kaffir lime (dwarf)
  • Pomegranate (full-sized)
  • Aniseed myrtle & Cinnamon myrtle
  • Acacia (various, all shrubs rather than full-sized trees)

The plantings were carefully designed in advance to ensure that we get the most out of the trees, with the least maintenance work:

GCADPlus drawing

The design was laid out accurately on the ground using triangulation, to ensure that reality matched the plan.

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Triangulating the position of each plant, with two tape measures

After planting, the patch was sheet mulched, with a layer of cardboard covered by hardwood chip mulch. This should keep the weeds down long enough for the cover crops to do their work.

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Sheet mulching the patch with heavy cardboard and wood chip

A few notes on the approach, with references back to Jacke’s book:

  • The planting is done in patches, with are then combined to create the overall garden design.
  • In this instance, it’s a polyculture patch (design pattern #44 from the book), which is a set of complementary plants that support and assist each other.
  • As outlined in our post on citrus guilds, there’s a big focus on nitrogen-fixing plants to support the hungry fruit trees.
  • The diagram above shows the eventual size of the trees (which will be some years off), and to achieve this an approach of instant succession (pattern #31) has been taken. This involves interplanting the gaps in the short term, to direct the eventual outcome.
  • There are at least three layers in the patch (pattern #38), from ground covers, to the dwarf citrus up to the pomegranate (which while full-sized, is deciduous).
  • A lumpy texture (pattern #39) of larger and smaller plants gives better light access, and confuses the pests.
  • I’ve used a number of native species (pattern #43), including acacias (for nitrogen-fixing), plus aniseed and cinnamon myrtles (for culinary purposes).
  • Underneath all the plants will be a thick ground-cover layer (pattern #49) that will be a mix of flowering plants to attract insects (pattern #42), and further nitrogen-fixers.
  • The patch was fenced, with five strands of tensioned wire. This should deter the wallabies and wombats (note I didn’t say stop the animals, as that would be optimistic!).

All the preparation and planting work was knocked off by dad and myself in three days, making it about a man-week of work in total.

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The finished patch, in the last of the afternoon light

Phew! It’s been hard (but rewarding) work this week to get our first patch in place. I’m sure there will be huge successes and crushing failures to come, watch this space!

Pickling large cucumbers

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Late in the season I planted two cucumber plants, with no great hopes for them. In Sydney’s hot and humid climate I’ve found that cucumbers, zucchinis, etc are killed off by powdery mildew long before they produce any real crop.

This time was different, and we were quickly overwhelmed by a glut of cucumbers, some of which had grown quite large.

Sandor Katz to the rescue! His book Wild fermentation — which really kick-started the recent fermentation movement — provided a useful recipe for sour pickles.

Undeterred by the fact I didn’t have lots of tiny “pickling cucumbers” I instead cut my big cukes into thin half-discs. The recipe suggested including grape or oak leaves to keep the pickles crisp, so I scavenged some oak leaves from the convent next door.

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A big jar of cucumbers, with an airlock to keep out the air

Into a big jar went the cucumbers, along with peppercorns, garlic cloves and dill flowers. I added an airlock, and left it to blip away for 3 weeks. And they behaved themselves perfectly: they didn’t bubble up and out the airlock, no mould grew on the surface, and the cucumber slices kept their shape.

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Three jars of piquant cucumber slices

We ate some slices today on a ham sandwich, and they are delightfully tart. Another win for Sandor, thanks!

Giving breathing room for two of our fruit trees

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It always amazes me to see trees planted by themselves in a sea of grass.

Not only does the grass compete fearsomely with the trees, but the grass encourages a bacteria-dominated ecosystem in the soil rather than a fugal ecosystem, which trees require. Trees also prefer to live in a tightly-bound forest of their peers, where their roots are interconnected, making it possible for them to share resources.

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This is one very sad fruit tree!

No wonder then that the two lonely fruit trees planted at Lewisham Farm have been struggling. We think they might be peaches, but we won’t know until we’re able to get them to a point of being healthy enough to fruit!

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The grass is easy to lift up around the tree

The starting point is to cut away all the grass directly around the tree. We then sheet mulched with cardboard, and then weighed down with wombat poos (which we have many of, which is another story!).

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Sheet mulching, with left-over moving boxes. Recycling in action!

(As a side note, there is a danger that the sheet mulching could stop water getting to the roots of the tree. In our case, the farm gets heaps of rain, the ground is well and truly moist.)

The trees will need much more help than this, and they’re also heading into winter dormancy. Still, it will hopefully give them some breathing room, while we find them a better home on the farm…

Constructing our first compost pile at the farm from pallets

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If there’s one thing that gardening produces a lot of, it’s green waste that needs composting. So while we have a small compost bin for the farm’s kitchen scraps, a proper compost pile is needed for the garden, even at this early stage.

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There’s no shortage of free pallets from the local retailers in Nowra

One of the easiest ways to create something fairly solid is to assemble a compost bay from pallets. What’s nice is that pallets are a free resource (the unbranded ones that is), which can be obtained (with permission!) from the loading bays of many shops.

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One of the back corners of the compost bay, screwed together and lined

The pallets are quite easy to screw together, to create a bay that’s two pallets wide, and two deep. Cover the inside of the pallets with shade cloth (or equivalent) to stop the compost falling out.

A half-size front makes it easier to add to the pile, and this is just wired on, allowing it to be easily removed when the compost needs turning (or harvesting!).

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The completed compost bay, already half full with garden waste

We’re only a few months into our farm adventure, and already we have a good-sized pile that should be ready by spring or summer. Happy days.

Our first harvest of dragon fruit

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It’s been a while since we’ve done a “first of” post. We did many during the first heady months of establishing our first proper veg patch, when every harvest is new and exciting. After time, of course, it all becomes very routine and not worth mentioning.

Still, dragon fruit is a pretty spectacular thing! We were given a piece of this succulent by a friend, over five years ago. Since then it’s clambered up our fence and into the tree, but only now has it started to fruit.

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Three yellow and white dragon fruit flowers

The flowers are distinctive, and they bloom for only a very short period. A few weeks later, we had three bright red fruit standing out against the green of the plant, and the grey of the fence.

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Ripe fruit ready for harvesting

A possum eat one, but we still ended up with two fruit. We cut them up to use in a fruit salad, combined with a harvest of mangoes and some yoghurt, yum!

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The unique black and white flesh of dragon fruit

This is just one of the sub-tropical plants that I’m starting to grow in Sydney, as we seemingly shift inexorably away from a temperate climate.