Bio energy


Bio-energy in general
Biological materials can also be converted into resourceful gas. If the remains of food, animal waste or treated in special tanks without the supply of oxygen, methane is formed. Meta gas can be burned and used for heating and to produce electrical energy. This is done on farms and waste places in many countries and also some places in Norway. In some Norwegian farms use methane gas from the stomach to the cow to heat up the barn. You can also create bio-energy in liquid form, either ethanol or Biodiesel.

Bio-energy in Norway

Leaving aside water energy as bio-energy is the largest renewable energy source in Norway. Here we get 16-17 TWh from bioenergy each year. This is enough to cover 6% of our energy consumption, but we can still increase the proportion. For example, we cut down only 1 / 3 of growth in the forests around in Norway. Bioenergy is the alternative energy source that is regarded as the cheapest for us in Norway to use, at least in the short term.



Biodiesel is bio energy in liquid form. It made by transesterification of vegetable oil, which can be used (alone, or blended with conventional petro diesel) in unmodified diesel-engine vehicles.
Biodiesel can also be made of used deep-frying fat, which is used when frying chips. This used deep-frying fat oil has to be cleansed for chips remains. When it is cleansed it can be used as biodiesel.
Some oil companies mixes biodiesel with petrodiesel. At a gas station you may see a signs like B5, which means the diesel of consists 5% biodiesel and 95% diesel.
The pollution from biodiesel is smaller than it is from regularly fuel. Fossil fuel (oil, gas and coal) uses thousands or millions of year to form, and then is taken out of the carbon cycle and the balance becomes unstable. When we heat with biological material, you also create CO2. But this is from materials that’s anyways going to rotten and leave CO2 in the atmosphere.


Ethanol is a pure and pretty reasonable biofuel and is used in some countries, for example Brasil as fuel to vehicles. The ethanol is usually made from sugar pipes or wheat/corn-based ethanol. Ethanol made of sugar pipes has a total 80–90 present pollution of CO2 than what fossil fuel has, while wheat/corn-based Bioethanol reduces the pollution with 30–60 present.

Problems with biodiesel and bioethanol
Some countries in Europe produce so much corn that the government wishes to use some of the areal used for farming to grow plants for biological energy aim, for example for making biodiesel or ethanol. At the same time we now millions of people in the world suffer from lack of food. With a growing population in the world, it will become more important and harder for us to produce food for everybody.
That’s why cultivate of biodiesel can get in a conflict with the need to produce enough food.

Bioethanol has also its down sides. It is considered damaging for the rainforest, because some parts of it are cleared to make space for production of sugar pipes, which instead could have been used to use for making food.

Biogas refer to a gas that is produced by nature's own decomposition of organic matter in the atmosphere without air, for example. in marsh, landfills or manure piles. The process takes place anaerobe process is biogas which is mainly methane (CH4) and carbon dioxide (CO2). Biogas can also be recovered from fertilizer or possibly in combination with other organic material (waste). It would then have a CH4-share of approx. 60 percent. It is also possible to produce biogas from old garbage, so-called landfill gas. The gas is then something more complex and has a CH4-share of approx. 50 percent. The most common is to create biogas of fertilizer, sludge, remains of food, fish waste, energy crops (wheat, corn, raps), but in principle can all organic materials used.

Biogas can be used to produce electricity, heat up buildings and cooking so called CHP (combined heat & power). Biogas is being transported in pipes, which makes it easier to transport it through longer distances. And If you upgrade the gas by cleaning it for CO2 and compressing it, it can achieve quality and natural gas used as fuel in the gas-driven cars,

(picture: process of biogas)

Breivika heating plant
Big heating plants for biomass is more suitable to warm up big buildings, fabrics and intuitions were the up warm water is transported around. The profit is biggest then, because it’s easier to transfer the heat. In short terms, heating plants for biomass warms up the water with combustion, and then the water is transported through a system of tubes and radiators.

We were on a visit at Breivika heating plant. There they use wood chippings as firewood to warm up the water. Troms Kraft, which is the company who owns Breivika heating plant, has plans to build a similar plant as Breivika, but they are going to burn food waste. It’s the same principe, but the use scraps of food instead of wood chippings to warm up the water.

(Picture: wood chippings)
The process is pretty complex. First the wood chippings is transported to the plant and emptied into a silo. From there the wood chippings are transported to the fire chamber. When the wood chippings arrives the fire chamber, it will be a victim of 800 degrees. At Breivika heating plant, they supervise the combustion if it optimal, if there is enough oxygen etc.
Above the fire chamber there is a big steam boiler, which is filled with water. The heat from the fire chamber warms up the water in the steam boiler, which becomes steam.

(picture: fire chamber and the alternating boiler)
When heat from the wood chippings goes through the steam kettle that is filled with water. The smoke from the oven to heat the water in the kettle. The water is converted to gas form that goes through pipes When the steam leaves the kettle goes some of it up to UNN where it is used for various processes (sterilization, ventilation, etc.), but most of the vapor is used to heat the water district to come back from customers, To be pumped out of the heated district heating network again. The air then come back again going through a filter before it comes out through the pipe. The filter consists of 110 each cloth bags that are about 3 feet long. Emissions are pushed through the bags so that what is of the dust particles get stuck on the outside of bags. At the end of each bag is a JET that periodically sends a pressure wave of air into the bag so that the dust that are mounted on the outside of the fall. These dusts then fall to the bottom of the filter and are fed to a separate collection container. The dust will then be delivered to approve disposal site. The smoke is in this way very effectively cleaned. The visible smoke of the pipe, therefore, consists only of water vapor from Ceres that burn. Ceres may periodically contain large amounts of water (over 50%) which provides a powerful off-steaming from the pipe. Temperature and humidity effect on the amount of water vapor that is visible (more on cold days).

This type of bio energy plant has a big potential. It’s more environmentally friendly than heating oil, and it does not disturb the cycle of carbon. It’s also almost impossible to use more wood to combustion than groves. It’s also much cheaper to buy wood chippings than buying heating oil. That’s why there should have been more plants like these.

Benefits of using bio-energy
- Renewable power
- CO2 neutral
- May solve the refuse problem
- Not very expensive
- Easy to find, and it is almost impossible to use more biological material than what grows up
- Balanced use of bio-energy pollutes very little.
- Bigger opportunities to expand agriculture
- Heating plants combustion biological mass easier and more reasonable
- Cleaner environment because of the combustion
- Less dependent on fossil fuel

- Big investments
-Increased use of biofuel can meet the problems in and with a growing world population. Areas will have to be used for food production in the present for the production of biofuel.
- Unreasonable use will lead to significant NOx and particulate emissions. With the use of modern facilities will be able to reduce these emissions.
-Livelihood of some people may be affected when the trees in large quantities disappear