self sufficient life

Aquaponics

My aquariums have a healthy balance of fish and plants. The water is crystal clear and the plants are thriving. I don’t have to do any water changes to keep all levels in the optimum range, the only thing I have to do is top up the water every other week to compensate for evaporation. A well balanced system like this is easy to create and maintain in an aquarium. It takes some experimenting, but once you get the hang of it the maintenance is next to nothing and you can just sit back and enjoy watching the fish.

Intensive fish farming is a different ball game. If you want to make a profit you have to put a lot more fish in your water. The water gets polluted by the excrements produced by the fish, making the water toxic for them. Bacteria that live in a biological filter can convert the highly toxic ammonia into nitrite and nitrite into nitrate. High concentrations of nitrate are still bad for your fish, but they are an excellent nutrition for plants!

You could use the nitrate rich water to fertilize the soil in your vegetable garden and replenish the fish tank with clean water. This would however require a lot of fresh water and a big part of the nitrates would sink deep into the soil, beyond the reach of your plants roots.

The solution here would be hydroponics. In a hydroponics system you grow plants in water instead of soil. The water in a hydroponics setup is enriched with nutrients that the plant roots normally extract from the earth. Small crops like salad and herbs can be grown on a raft that floats on the water and has holes in it for the roots to reach the nutrient rich water. Bigger crops like tomato plants need some coarse gravel or rock wool for support. This grow medium is located in a tub that is flooded with the nutrient enriched water. After the growing plants have extracted the nutrients from the water it has to be enriched again.

Hook the fish farm up to the hydroponics and you have an aquaponics system. The fish provide fertilizer for the plants and the plants clean the water for the fish. The balance in an aquaponics system is much like in my aquariums but both the fish and plant density are much higher. As long as you make sure that this balance is maintained, you can make the aquaponics system as big or as small as you want, ranging from one small fish and one plant to a pond with thousands of fish and an acre sized greenhouse.

A big commercial system isn’t for everyone, but you can have a small aquaponics system in your garden or kitchen made out of items you probably already have laying in your garage or shed. Put a little work into it and you can enjoy home grown fresh herbs and vegetables, without the pesticides!

Looking for information on the subject, I stumbled upon the Backyard Aquaponics Forum, which turned out to be a very friendly community of people with a great deal of knowledge and experience in this field.

Generate your own power

I dug up some old electricity bills the other day to check how much juice we have been using over the past few years. I was shocked by the numbers I found, we use about 10500 kWh a year which equals a constant load of (10500 kWh / 365 days / 24 hours =) 1.2 kW or 1200 Watts. The power usage itself isn’t the shocking part, considering we use electricity to cook on, have a bunch of other appliances that are used regularly and a few tropical aquariums, one of which is a saltwater aquarium which has some quite powerful lights and pumps. What did shock me was to see the total money spend on electricity. With a kWh costing about 24 cents, the total yearly cost for our electricity usage ads up to 2.5 grand (that is Euros, which equals about 3,700 US$!!!)

There are better things to do with that kind of money but we still need the electricity. Sure, we can probably cut down on usage, but quite frankly there are not a lot of electric comforts I want to give up. I will use an average of 1000 Watts of power usage to figure out what kind of power plant we need to build. If I take into account the small fish farm we might want to start, that adds another 1000 Watts.

I’ve already ruled out solar power because the up front costs will be too high. I do want to tap into the power that the sun delivers for free, but I will use that for heating instead of electricity generation. Wind power is another free source, but since it depends on the weather conditions I’m not too keen on that either. I will probably experiment with wind power in the near future but for now I need a better, more constant, source.

I am having a closer look at Lister-engines and the more I read about them, the more I like them. A Lister CS (cold start) engine is a diesel engine that can deliver great power for very little cost. These engines are build to run for decades, I’ve read about some that have been running 24/7 for over 40 years! And the required maintenance is very low. These engines run at low speeds of 600 – 1000 RPM, making them less noisy than regular diesel generators.

Running an engines like this hooked up to a 10 kW power generator for about 5 hours a day would be able to cover my total power consumption. The heat generated by the engine can be fed back into the central heating system. Using the generated heat would be another big money saver considering the huge increase in oil prices, currently at $95 a barrel vs. $52 per barrel in January! The oil price does not affect the running cost of the generator as it can run on waste vegetable oil, which can be collected from local restaurants for free. The restaurant owners normally have to pay to get their used cooking oil disposed of.

Since the electricity generated by the generator would be somewhat constant while it is running and the usage has spikes as appliances get turned on and off, a buffer is needed to store the generated power, so it can be used at times when the generator is not running. One way to store your electricity is in batteries, but since most homes here are connected to the electric grid, we can just use that! Solar systems are often hooked up to the grid like this, by using a special electricity meter you can have the meter run backwards when you generate more power than you use. If we feed enough power back into the grid we can start sending bills to the power company, much better than receiving their bills!

Catching the sun

One freely available green energy source is the sun. It shoots its power-packed rays at the earth every day, all we have to do is catch them and convert that energy into a form that is usable. Solar panels that convert the sunlight into usable electricity cost a lot of money. They do pay off in the long run, but the up-front costs are just too high for us. There are other ways to use solar power though.

I am looking into using the suns power to heat our water. A solar water heater can be home-made for a fraction of the cost of a commercial unit. The design and construction doesn’t require any special knowledge or tools and the materials needed can be bought at any hardware store. What we have to make is a big box, with a glass (or plastic) top that allows the sunrays to enter. The inside of the box is painted black because black absorbs most of the light (and heat!) Sound familiar? What we have is basically a solar oven. Now all we need is to run our waterline through it, so the water can absorb the heat. To give the water passing through the heater time to absorb heat it should flow at a slow rate. We can easily slow down the flow rate by dividing the total flow with a manifold and using a second manifold at the exit to combine the different pipes again.

Fish farming

I have enjoyed keeping fish for a long time. Looking for something that could make some money in the winter time, when crops don’t grow on the land, fish farming sounds like a good option. There are several species of fish that could be breed economically in our central European region. I would probably keep carp, tench and zander.

Fish farming can be done in two ways: extensive (pond) or intensive (closed-circulation) Extensive aquaculture requires very big ponds that are lightly stocked. You will need about 15 square meters (160 square feet) of pond surface area for each carp. The total water volume doesn’t really matter since the food supply in the pond is following the natural food chain, starting with the algae growing in the sunlight hitting the pond, making the surface area of the pond the limiting factor for how much fish you can grow.

With intensive aquaculture you can keep as many fish as you can fit in your body of water, as long as you make sure that the water is clean and that there is enough oxygen and food available for the fish. To keep the water clean and oxygenated a good filtering system is needed and a set of pumps to move the water through the filters.

Since a patch of land that is big enough for extensive fish farming would just cost too much, I will work with a closed-circulation system. I will have to look into the total cost of different systems. The cheapest option would probably be digging a big pond, but the fish production would be limited in the winter time. A more profitable system would consist of indoor ponds, making it possible to achieve maximum growth year round.

Living off-grid

Being self-sufficient typically refers to being able to provide your own food. When looking at utilities, like water and electricity, being your own provider is called living off-grid. While growing crops and keeping animals for food takes a lot of time and work, being able to cover all or part of your electricity and water usage is far easier. After the initial planning and installation an independent power or water system will only require a bit of maintenance every now and again.

People live off-grid for a number of reasons, some choose to, to save money, while others are forced to because of their location. What ever the reason, good planning beforehand can save a lot of trouble and grief down the road. The most important things to think about when planning your off-grid system are location, requirements and cost:

Location

Your location could narrow down the choices you have, running a diesel generator in a one bedroom, downtown apartment is something that I would not recommend. Local building regulations could come into play when you want to build a wind generator.

Requirements

How much power do you really need? Starting point should be your current power usage. The less power you need, the cheaper your system will be, so have a serious look at what uses all that electric power. Maybe there are some things you can do without or different. Things like a dryer take a lot of power to run, you could just hang your clothes on the line to dry and save some power. Electric stoves also need quite some power, a good alternative would be a gas stove. How about that big screen TV, do you really need that?

Make a list of all the electric devices you have and check how much power each of them consumes, they should all have a power rating on them somewhere. If you multiply the wattage of each device with the number of hours you have it switched on each month and divide that by 1000 you will have the total power consumption of your electrical device a month in kWh, which is the same unit of power that you can read on your electricity meter and electricity bills. For each device you should have a good think about whether you really need it or could live without. The devices you do need could have an alternative that uses far less power.

Costs

For most people the limiting factor is costs. You can have all the power you want from solar cells or a fancy big windmill, but these devices cost a lot of money. In the long run they will save you money or even make you a healthy profit, but the high up-front cost is more then most of us can handle.

A lot of people have build their own windmills from scrap with great success and share their experience on the internet for free. Find all the information you can and learn from the mistakes that others have made, so you don’t have to make them. I am still figuring out how much power our family would need to live off-grid. After that has been done, the search for our perfect off-grid system can start.

(note: the windmill picture was shamelessly ripped from The Back Shed)

How much land can feed a family?

After reading about people using several acres of land to be self-sufficient I started wondering how practical it would be where we live. A little more research on the subject lead me to a great article by Greenspree, which takes a detailed look at how much food a family needs and the yields per acre for different types of crops.

The bottom line of the article is that about a quarter of an acre, which is roughly 1000 square meters, can provide most of the vegetable needs for a family of four. Agric says that only about half of that area is needed to be self-sufficient, which sounds realistic, because you can plant different crops on the same patch of land at different times of the year.

The Crop Yield Verification sheet used for the calculations by Greenspree contains a big list of different fruits and vegetables that you can grow and their yield per acre. What I found interesting is the relatively high yield of apples and pears and when planted in the middle of a nice patch of grass where the kids can play, they don’t take up any of the space of your vegetable garden. The only problem with fruit trees is that they need quite a few years of growing before they produce food, so these should not be taken into account when figuring out what we can grow.

I have put 1000 square meters for growing crops on my list of requirements. This should be able to provide my family year round with vegetables and leave some extras that can be sold on the farmers market to bring in some cash to buy things that are not practical to grow on a small scale.

Welcome to the self-sufficient life blog!

We have decided to leave our city home and start a new life on a farm far away from all the noise and pollution. One thing to consider when moving is job opportunities and after some thinking I have come to the conclusion that life without a regular job could be a feasible alternative.

The time normally spend at a job could be used to work on the land, growing vegetables, fruits and herbs to feed our family of four. We don’t want to go Amish, so being completely self-sufficient will not be possible. There are a few things we don’t want to live without, quite a few actually, meaning we have to make some money.

The amount of money we need depends on how much we can do ourselves. With food undoubtedly being our biggest cost at the moment, that will be the first thing to look at. Growing most of the food should not be a big problem, the only question is: how big a piece of land is needed to be able to grow enough food to survive?

I have started this blog to keep track of my investigations on the subjects of self sufficient life and off-grid living. Over time this blog should grow into valuable resource for myself and anyone else interested in the subjects.