ABC of renewable energy

Renewable forms of energy are here to stay, and it is good for each of us to know more about the production and benefits of emission-free, renewable energy. In this article, we’ll tell you what every tavis should know about the subject.

What is renewable energy?

Renewable energy refers to energy from non-fossil sources, such as wind and solar energy, geothermal energy i.e. heat stored beneath the surface of the soil, environmental energy (air, surface water, wastewater), tidal, wave and other ocean energy, hydropower, biomass, gas and biogas from landfills and wastewater treatment plants.

How are renewable energy sources converted into energy?

The kinetic energy of wind can be converted into mechanical energy. The wind rotates the blades of the power plant, which rotate the shaft of the power plant, and the shaft further rotates the generator, which produces electricity.

The production of solar electricity is based on the utilisation of solar radiation energy. Solar radiation consists of photons, i.e. small particles that carry radiation energy. When particles hit solar cells, they give up their energy to electrons in the cell material, which form an electric current in the current conductors of the solar cells.

The kinetic energy of the water flowing in the waterfall of the hydroelectric power plant is captured as the water goes down and flows through the turbines. Kinetic energy is converted into electricity in generators and led through a transformer to the power grid for consumer use. The operation of the hydropower plant is based on the height difference between the upper and lower basins of the power plant. The waterfall can be natural or connected by dams and waterways from several sections of rapids. 

What other factors influence how renewable energy is deployed?

Environmental, construction and expropriation permits must be applied for the construction of renewable energy. For example, when constructing wind power, in addition to the usual impacts related to the environment, natural values and housing, the possible effects of the height of wind turbines on air traffic, the Finnish Defence Forces and the functioning of communications networks must be taken into account.

The use of renewable energy is also affected by Finland’s energy and climate policies and decisions and directives made in the EU, such as the Emissions Trading Directive and the Renewable Energy Directive, which aims to reduce greenhouse gas emissions. The price of carbon dioxide emission allowances increases the cost of fossil fuels used to produce electricity and makes them less profitable. Producers of emission-free energy do not have to pay for carbon dioxide emissions, which improves the profitability of renewable energy and thus increases its use.

The amount of renewable energy could be increased if people invested in it both as private investors and companies. The transition to renewable energy would be accelerated by a support scheme that would encourage investment in newer and less exploited technologies. At the moment, at least battery park construction is covered by subsidies. Ilmatar will also receive support in the Alajärvi hybrid project.

Why is renewable energy important for Finland?

When the share of renewable energy is increased, the need to import energy from other parts of the world decreases. This will increase Finland’s self-sufficiency in energy production. Succeeding in achieving the carbon neutrality targets requires investments in renewable forms of energy. Finland would have an excellent opportunity to set an encouraging example to other countries.

What are the key benefits of renewable energy compared to fossil fuels?

The production of renewable energy reduces the need to burn fossil energy sources that cause high greenhouse gas emissions. As the name implies, renewable energy sources are renewable, so their sources are not depleted when used sustainably, unlike fossil energy sources.

Why should a layman be interested in renewable energy?

When you buy renewable electricity and heat, it reduces your own carbon footprint and also sends a message to energy producers that it is worth investing in renewable energy sources. However, the best way to reduce your carbon footprint is to use as little energy as possible.

Microgeneration is an ecological and, when sensibly dimensioned, economically viable way to produce electricity for one’s own use. For example, solar panels installed in a detached house increase the value of the property. It is also possible for citizens to produce small-scale wind power that can be used by themselves, stored or even sold to the electricity grid.

What does the future of renewable energy look like in Finland?

Finland is among the leading EU countries in the use of renewable energy. So far, renewable energy has focused on the use of wood and bio-based recycled fuels in Finland, but the amount of renewable energy in total energy production will grow considerably. A huge number of wind power projects are underway, and new ones are being mapped all the time. The number of new photovoltaic power plants will also increase in the coming decade. 

Megawatts of renewables in everyday life

Below are calculations illustrating renewable energy coverage. In this kind of calculation, default values or assumptions must be used instead of correct production or power data, which only provides indicative estimates for different scenarios.

How many EVs do you need to charge with one turn of turbine blades?

If we consider as an imaginary example a 5 megawatt turbine with a blade rotation speed of 13 revolutions per minute at its nominal power, then about 8 revolutions would be enough to fill a 50 kWh electric car battery from empty to full.

How many TVs will be consumed annually by a 6 MW turbine with the latest technology?

If we imagine that one television is kept on for 3 hours a day and one television consumes 0.25 kW of energy per hour, then the energy produced by one turbine over the course of a year covers the annual energy consumption of approximately 63 400 televisions.

How many hours of solar is needed for the electricity needs of one detached house per 100 MW solar park?

If one detached house consumes, say, 20,000 kWh of electricity per year, and the solar park produced 90 MWh of electricity per hour at a sunny moment, then the electricity need of a detached house would have been covered in just over 13 minutes.

How many offshore wind turbines are needed to cover Helsinki’s electricity needs?

If the nominal output of an offshore wind turbine were 10MW, the electricity consumption in the Helsinki urban area would be produced by approximately 116 wind turbines.