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.

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.

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)