When we started out thinking about building a house a few years ago, we had a lot of good potential plans. Mine mainly involved tires, Eug's involved straw. The challenge with these building styles was time and money, while not living on site or doing the building ourselves up to now. It's been a really interesting figuring out what might work with our current resources. We've saved for quite a few years for this, but getting to something even more ideal might involve a leap that is beyond our faith/ability/financial means right now.
We didn't have the bandwidth to physically build our own house in the next few years. So we hired builders, and we've chose a light steel frame structure, which is relatively quick to build and light on materials, and supposedly well-insulated. Some stuff is recycled (insulation, some stuff that we managed to get secondhand like doors etc). But for the most part, we've tried to plan for the smallest house we can, both for cost, efficiency, and because we don't want to have to clean a big house.
Building-- even a small house-- is not cheap (though I'm sure it can be if you're wiser or in a different life stage than us). For full disclosure and if you're trying to find your own way through this process, this house will likely cost about R650,000 (including the cost of getting us off-grid) before we're done (US$54,000). In a cheaper part of the greater Cape Town area where our plot is located, you could buy a larger house for a similar price on a small lot/erf (our land cost +house cost is about R1.53 million, or US$127,500). But we simply couldn't afford a ready-built house with land. This is partly because if a property has an acre of land, it's likely to have a [large] house on it already, and cost upwards of R4 million (US$333,000). We also got one of the very last 1 acre plots in the Masi area (or any area in the southern peninsula)-- since we bought, there haven't been any similar plots available. All to say, we have nothing against ready-made, brick and mortar houses. Oftentimes, ready-made is the more sustainable option. It was just that we really wanted a farm.
Our house is not going to be the perfect low-impact house, but I wanted to write about process nonetheless. Because we feel like while our choices aren't perfect, we're similar to some of our readers so maybe our experience will somehow be helpful. There's something to be said for an approach that stretches us far as we can reach right now, while recognizing that our best efforts have massive blindspots.
So if it's not a perfectly sustainable house, how have we been making decisions about energy/water?
Solar (PV) systems in Cape Town
Solar energy (for electricity) works pretty well in Cape Town-- we have quite a lot of sun 9 months of the year. Once energy needs get close to middle-class average use, however, it's super expensive to cover winter needs (with excess wasted in summer), so most people go with a grid-tied system, which allows them to use electricity from the Eskom grid when they need to, and feed energy back into the grid when they don't. As far as I can tell, this is very expensive and problematic. Better, perhaps, to have the two completely separate systems if a household is connected to Eskom. Partly because we're suffering frequent power shortages nationally, solar power is very popular. There are also a lot of consultants who can help set up a system, but we found that this added absolutely massive expense so we decided to calculate our needs ourselves. It's a bit of a free-for-all.
We wanted to stay relatively small and also stay off the Eskom grid. Our needs are still decidedly first world, but we're working on it. We will have a gas stove/oven, a small wood stove/fireplace, and a solar water heater. So the PV panels are for the washing machine, freezer, bar fridge, laptops, modem (maybe), (non-smart) cell phones, water pump and LED lights. In our old house, we used about 3kWh of energy/day The costs for a system that should power these things most of the year was about R37,000 (about $3080). Maintaining battery life on an off-grid system takes some management, so we have to change our electricity usage according to the amount of energy available-- which might mean going without electricity some of the time.
In our case, we're not saving money by going with solar energy. I don't think most consultants are telling the truth when they claim a system pays for itself super quickly. Our energy costs in our previous house were only about R80/month, so it would take a long time for the system (uh... minimum 20 years?!) to pay for itself. This is without factoring in installation costs, and avoiding the consulting fees solar companies charge. On the other hand, we're not paying for our system out of future electricity bills. We're paying up front, using money we'd otherwise use to make a larger or nicer house. But still, my opinion is that it still doesn't make much sense to do solar PV panels to save money. It does make financial sense to have a solar geyser/water heater, in most parts of South Africa. These days, the technology for a solar geyser is really good, they're pretty inexpensive, and you can get an eskom rebate if your old geyser is removed. They're also very simple-- the sun heats up water in a panel or tube, which circulates into a tank. There are also some great DIY solar water heating options that are even cheaper. So if you're just starting out, considering solar water heating is a great option.
Solar panels are not a perfect energy source, so it's not like you can just use a crazy amount of energy and pat yourself on the back for using solar. There is a lot of debate about the energy used to make solar panels-- in fact, it was only pretty recently that solar panels generated more energy than was used to manufacture them. We're not only using solar energy-- we're also using wood and gas. Our woodstove is able to use very small pieces of wood, so there's a hope that we could use waste wood, and also use a DIY solar oven to decrease our use of gas (we currently use a lot of gas for cooking). Still, balancing our own need to feel abundance with the need to be good stewards is pretty complex stuff, and in our case it's a gradual process, where we sometimes go forwards, sometimes backwards.
We've decided to get some municipal water, partly because the city provides 6000L of clean water to every household, free, every month. We hope to make minimal use of the water, mainly while we're still on a steep learning curve with our rainwater system. As with electricity, we will work on keeping our consumption low, but we also wanted to use whatever resources we can to help bring our farm an even supply of water year-round, particularly in our first couple of years. Unlike electricity, where we can go without, water shortage would result in hardship. I think there may be a time when we're convinced it's important to go without municipal water, but not yet. Having clean drinking water sent to our kitchen also allows for a relatively simpler water system.
From our kitchen, municipal water can be fed into one of our water tanks if rain has not been sufficient to fill up a tank. We're going with one 5000L and one 2500L Jojo, the basic, plastic tank used a lot in southern Africa. We don't know how much water we'll use: how much to water our trees, how much our own usage will change as our kids grow up, etc. We're not using a flush toilet for the first time in our lives, so that will significantly reduce our water use-- but then we're still not sure of how much we'll need. The water in our tank will be pumped into a low-pressure solar geyser/water heater on the roof. Hot water will be primarily available in our bathroom, where we'll be using rainwater unless there hasn't been rain. The washing machine will also use rainwater.
As backup, we have planned a couple of projects involving borehole/well water. Borehole water is free once a wellpoint is constructed, but if people overuse the water obviously it's a major problem. So we're going to try to build a hand-operated pump ourselves and also set up an electric borehole. We're waiting on these until the rain starts to dry up and we need to begin watering our trees again (and hopefully by then we're living on the farm and know how much money we have left).
All our greywater will be fed into mulch-filled ditches. Most water coming out of the bathroom is pretty clean, so it will be fed directly to our annual garden. The water coming out of the kitchen (sink and washing machine) is more dirty, so it'll go into reed-filled ditches to our food forest. I'm hoping that the reeds will grow quickly so we can use them for mulch every year.
|Random tree interlude: Naartjie, almond, blueberry, banana, fuji apple, star ruby grapefruit... waiting to be planted.
When we tell people we're going to have a bucket toilet, it tends to freak people out. I'm not sure we're going to have many visitors. Please, don't be afraid, come and visit! If it goes badly (i.e. if it smells-- which the system is not supposed to), we'll figure something out!
I've been reading about composting toilets for several years now, and the best book on the subject is the Humanure Handbook, available online free in pdf form. Joseph Jenkins argues that the best system is the simplest one (so no concrete lined rooms below your bathroom-- hooray!). The main part of the bucket toilet that makes it non-smelly is sourcing abundant, carbon rich, cover materials. With these cover materials, the toilet shouldn't smell. Once a week or so, you take the bucket(s) and empty them into a compost pile outside, where again, the new toilet material is well covered by carbonaceous materials (often hay). The compost pile outside also has a very thick layer of carbonaceous material on the bottom, so that no pathogens seep into groundwater, and the compost pile is left for a year before use in the garden/food forest. Once we move in I'm sure I'll share a lot about this process and our learning curve. It'll be new for us, and it's a bit risky-- we're not having a flush toilet as backup, so we are all in! But it makes so much sense so here's hoping it's successful.
There's uncertainty and a lot of work in front of us to finish our house before the new baby is born. It also feels like there's blessing we can claim in the process. Please pray with us for a smooth building process... We're really hoping to move in around the end of this month.