The use of energy in our homes is unavoidable, providing heating and electricity within the home. Traditionally, we have relied on fossil fuels such as coal, gas, and oil to meet our energy needs. Fossil fuels by nature are a finite resource and will eventually run out. In addition to this, they are harmful to the environment, contributing greatly to the production of greenhouse gases. The most important of these greenhouse gases is carbon dioxide (CO2): almost half of the energy related to CO2 emissions is derived from energy use in buildings.
There are numerous ways to reduce energy needs within the home without compromising warmth, comfort and overall standard of living. Renewable energy sources can help reduce greenhouse gas emissions and are also good for the economy because of the problems associated with the long-term availability of fossil fuels.
Renewable energy options for a homeowner include solar power (the sun), heat generated below the earth’s surface (geothermal), and wood and energy crops (biomass). In Ireland, several of these resources are abundant. The homeowner can do their part for the environment by opting for a renewable heating system that meets their needs in terms of heat demand, budget, and environmental considerations.
Biomass is all plant and animal matter on the Earth’s surface. Bioenergy is the term given to the collection of biomass, such as crops, trees, etc. to generate power.
In fact, Biomass was the first fuel that humanity learned to use when the first primitive fires started. Biomass has achieved an important participation in the energy market of the Continent. Ireland has one of the lowest uses of biomass in Europe, but has one of the largest resources. Biomass provides around 1% of the country’s energy needs in the form of domestic and industrial wood heating. Wood is a ‘carbon neutral’ fuel in the sense that it absorbs as much CO2 when it grows as it releases when it burns.
The main types of wood fuel are chips and pellets. Wood chips are a clean, low-moisture fuel made from wood in its natural state. They are a high energy, low smoke fuel. They are a bulk fuel, which means they are generally not suitable for domestic purposes due to storage issues. They are used in larger buildings or to heat groups of domestic properties through one heating scheme. Wood pellets are a clean, dry fuel made from a mixture of sawdust and wood chips. The wood pellets have a diameter of 6 to 12 mm and a length of 6 to 20 mm. The pellets are easy to ignite and leave little ash. A feed mechanism such as a hopper can be used to feed the pellet burner.
Similar to traditional gas or oil burners, a wood pellet boiler will provide full central heating and hot water. Wood pellet stoves provide heating for a single room. They produce a small fire that, concentrated in the center of the unit, burns hot.
Similar to traditional oil or gas burners, a Pellet boiler will provide central heating and hot water. Pellet stoves provide heating for a single room. They produce a small fire that, concentrated in the center of the unit, burns hot.
An important consideration when opting for a pellet burner is storage. Pellets are a bulky fuel, which means more storage space is required than oil. The warehouse must also be kept completely dry and free of moisture.
Hydropower is the capture of the energy of moving water for some useful purpose. The power of moving water has been exploited for centuries, but it was first used to produce electricity in the 1870s. The power generated from a hydroelectric scheme depends on the height of the waterfalls and the volume of water available. The water is diverted from a certain point in the river to a turbine house where a turbine converts the kinetic energy of the falling water into mechanical energy. A generator then converts the mechanical energy from the turbine into electrical energy.
Given its nature, the resource is very site-specific (even more so than solar), but if you’re lucky enough to have a stream nearby and have enough head (height between your source and your hydro turbine) and enough flow, then it’s a viable option. The issues to consider are the capital required in civil engineering works such as the dam and the water channel. Constructing a bypass and inlet that effectively removes debris and can withstand high seasonal flows can be challenging.
Ireland is blessed with a large amount of wind power. More and more large-scale wind turbines can be seen all over the country to meet the electricity needs of the country. Wind energy is clean, free and of course infinite.
For remote locations that have no connection to the power grid, a wind turbine based power supply will produce electricity much cheaper than the costs of bringing in power lines. Turbines large enough to provide a significant portion of the average home’s energy needs require at least half an acre of land. Factors that determine the viability of home turbines include wind speed and direction. Wind speed increases with height, so turbines will give better performance if they are placed at a higher level. The site should also have a good “look” to the prevailing wind.