Sustainable houses are based on the principle of sustainable development guided by the idea that all of your needs should be fulfilled so that they don’t endanger the benefits of upcoming generations.
Why sustainable construction?
Our energy consumption is increasing on a daily basis. Thoughtless, inefficient energy use causes a needlessly large energy production and therefore causes an unnecessarily large adverse influence on the environment.
The building energy rating is the number stating the yearly consumption of energy based on a unit of heated surface and it is portrayed in kWh/m2. The lower the amount, the better the heat protection. A typical building energy ratings are usually 0 to 30 kWh/m2 for an energy efficient house and over 200 kWh/m2 for energy inefficient buildings.
There are a few different categories of energy efficient houses: low-energy, passive and zero energy houses
The yearly need for heating a low-energy house is 20-40 kWh/m2. To be able to achieve that, those houses have good insulation, energy efficient windows and low air flows. Low-energy houses are also called “three-liter houses”, named after the fact that they use around 3L of oil per m2 a year for heating.
Yearly heating needs of a passive house are around 15 kWh/m2 or less and the overall energy needs for heating, warm water and electricity are less than 40 kWh/m2. A passive house has controlled ventilation system with recuperation of the air, heat and solar energy transformations.
A house with zero nett energy consumption and zero nett emission of carbon-dioxide is called a zero energy house.
Such houses can be fully independent of public energy networks. However, in reality, during winter those houses do receive some energy from city energy grids and during the summer months excess energy is returned to the grid. This evens out the energy balance sheet. Also, these houses don’t have a traditional heating system but rather use solar energy actively and passively.
Sun’s energy is a renewable energy source. The modern society has seen a lot of advantages in usage of solar power - lesser dependence on fossil fuels, better air quality and decreased emissions. Also, production and installation of solar systems opens new workplaces and stimulates economy growth.
Solar photovoltaic modules are used to directly transform solar energy into electricity to ensure enough power for direct and alternating current devices and appliances.
Solar photovoltaic systems enable you to be energy independent, their maintenance costs are low and have a lifespan of 30+ years, also increasing real estate value. Photovoltaic systems outside of energy grids, work so that they save a part of the energy into ACU batteries, while a part is used to power appliances. Saving energy into batteries enables everything to be powered when modules don’t produce any energy for ex. at night or during low - sun days. Photovoltaic modules that are a part of an energy grid use the low voltage grid to power appliances in a so called "interactive work regime". All of the energy produced is returned to the energy grid and that grid is used as an energy source. Roofs make perfect areas for installation of those modules as they are a large unused area directly exposed to sunlight
Solar photovoltaic modules produce energy directly from the sun and that's why they are an environmentally extremely acceptable as well as an economically interesting energy source. They have a long lifespan, and are easy to install and relatively cheap to build. Also, let’s remember that the sun is an unlimited energy source that doesn’t send bills.
Using solar collectors allows for the Sun’s energy to be directly transformed into heat. Collectors are placed onto a house roof and are used to heat up the water inside them. That water then flows through the pipes and heats up the house. Solar collectors are used to prepare warm water and to heat up space.
A solar system consists of a collector, a water tank and a regulatory system. Solar collectors are a closed system that transforms the sun’s energy into heat. With the aid of a pump for circulating solar liquid, the solar collector collects the heat which is lead to the tank through a heat converter. The water is then further transported to the house or accumulated in tanks for further heating. When the Sun's energy is not enough, the lack of heat can be substituted by using conventionnal fuel (biomass, gas etc.).
The most common question about solar collectors is whether there is enough sun throughout the year to justify the investment.
In reality, 2/3 of the Sun's radiation appears between May and August, supplying a 100 percent of total warm water preparation needs. However, the months of April and September are also not negligeable, as during this time, 80 percent of needs for sanitary water i smet. March and October can meet 50 percent of warm water needs.
Properly insulated buildings reduce heat losses during winter, as well as overheating the living space in summer. In addition, they offer protection from outside influences of the construction and temperature influenced stretching. This allows for healthy and optimal living conditions.
Inadequately insulated building leads to unnecessary heat loses during winter, when, due to a great temperature difference between the heated space and the environment, the heat from the building is lost through the construction elements (walls, ceilings, floors, door) which causes cooling of the building resulting in a larger need for heating, cooling and also in condensation. All construction elements need to be fully heat proof. Aging elements are replaced by newer more efficient elements (elements such as doors, windows) or they are being insulated.
OUTER WALLS - heat losses through outer walls can make up to 21% of overall transmission losses. Uninsulated walls need to be heat proofed by placing a layer of insulation or they need to have a bigger thickness of the current insulation layer (by using materials such as stone wool, styrofoam, poliester up to 20cm). Heat insulation should be placed on the outer walls, only if there is a construction reason why it can’t be done on the inner side.
Although they take up only a small part of the overall building construction space, windows provide up to 10 times less resistence to heat loss than walls do. Heat losses through windows make up to 50% of overall heat losses in a building.
Old windows should be replaced with multilayer isolation glass ones that have mid layers filled with air or any kind of an inert gas.
During summer months you should use blinds or curtains as sun protection. By doing so, you can ensure significant energy savings and a better atmosphere in a house. During winter months you should use blinds and curtains to keep the heat in.
The roof and floors of the house amount to 20% of heat loses (roof based loses) and 10% losses to the ground through floors. Angled roofs are usually insulated by placing insulation materials (glass wool or polyester up to 20 cm thickness) while the floors are insulated by placing materials on them as well (up to 10 cm in thickness).
Water is a unique and irreplaceable natural resource of limited and uneven availability in the world. Global climate changes can disrupt water’s natural balance and decrease the possibility of access to it in many areas, making water even more valuable. Earth is often called the water planet as 70% of its surface is covered by water, however only 1% can be used for people’s daily needs. Unfortunately, due to industrialization, irrational spending and high level of pollution, water is becoming an increasingly endangered resource.
In order to decrease water consumption in households, it is enough to apply small measures which can help save the environment as well as your own budget. Better control, greater vigilance and rational consumption allows us to save significant amounts of water daily. Needless dripping of two drops a second will lead to a loss of an unimaginable 6000 l a year.
Because of those and similar loses it is important to regularly check and upkeep all of the water-based infrastructure, as well as do maintenance such as decalcification of washing machines. Toilet tanks are by far the biggest water consumers in an average household and this is why the biggest savings can be achieved by incorporating a saving toilet tank in order to control the flow and amount of water going through. Water and energy savings can be achieved on faucets and shower heads by installing a stream regulator that limits water flow by adding air to water. This way you can save up to 70% of water and energy needed for heating water. Savings can also be achieved by installing a special thermostat that keeps water temperature a constant as well as placing an aerator to limit water streams.
How much water we use can also be lowered by installing a stop-shower; a small faucet mounted onto the shower hose. By doing so the stop-shower allows only the already heated amounts of water through. With bigger investments, you can install electrical sanitary facilities (most commonly used in public spaces) that allow passage of water only when faucet is used. There are a lot of different options available , but it is important to get informed beforehand in order to become familiar with the technical aspects of every solution.
The most efficient appliances are usually more expensive in the beginning, even though they use significantly less energy than the regular ones. However, when monthly maintenance and usage costs are summed up, their initial costs are justified. It only takes one look at the product’s energy efficiency class to get a better understanding of how much it will cost which allows the user to select the most cost-effective and efficient appliance. By reducing water consumption, the consumption of other energy sources is also decreased. This is especially true of electricity used for powering the pumps in water wells. Also, environment pollution and greenhouse gas emissions are also decreased, leading to a decrease of adverse effect connected with climate change.
Continuously growing consumer standards as well as a growing number of household appliances accompanied by growing electricity expenses, all contribute to a big influence of electricity on one's budget. Even though habits can be difficult to change, the first step towards rationalization of expenses is to save within our own household, which is possible without new investments. The amount of monthly expenses for utilities depends on the usage of appliances. The sustainable development concept, competition between appliance manufacturers and organized efforts by the European Union to determine the norm for the household appliance consumption will result in ever more energy efficient appliances.
Energy efficient appliances use up far less energy than standard ones and it is recommended to consider how much energy your appliances will need. This is why it is advised to buy appliances with energy level A. The difference in electricity use between an A level appliance A and D level appliance is about 30-45%. Energy level is a sign of quality regarding energy use of the appliance and in accordance with the Regulations of energy efficiency, appliances are categorized into 7 grades marked with letters from A to G. The most efficient appliances are in group A.
Household appliances take up the most significant place in energy balance sheet. All appliances are divided into 7 categories - A to G, where A stands for least usage of energy and G for most energy use.
Air conditioners allow to control temperature, humidity levels, cleanliness and air distribution. They enable us to create an environment where we feel the best, by choosing the right temperature. Not only do air-conditioners create you better comfort, they also help you feel refreshed even when outside conditions are more extreme. Air conditioners are getting more and more present in households and account for a major part of electricity usage in a home. They are considered big energy consumers. Smaller air conditioners can be divided into split-systems and compact ones. When all parts of air conditioners are in one housing, they are called compact systems and are either roof or window systems. However if there are two or more units they are called split systems (either monosplit or multi-split). When choosing your device or system it is advised to choose those with the highest class (A, A+).Even though cooling systems create a subjective feeling of what is pleasant, it is quite justified to ask how air conditioner usage influences your health. The answer to this is quite simple - air conditioners can be good for you, but only if used properly. Misuse can bring more harm than good. Key factors to consider for safe usage include: the place of installation, room temperature, frequent maintenance. It is advised to keep the difference between indoor and outdoor temperatures at no more than 6 degrees Celsius in order to keep health and electricity issues low.
Energy efficient use of lights pertains to using as much daylight as possible, as daylight is the best light source available. It also allows lighting up the entire ambient such as your work place and provides contact with your surroundings. Artificial lights enable you to continue your daily activities when daylight doesn't provide enough light or during the night.
Use of artificial lights can't really be avoided in day to day life, but it is important to try and reduce its use to the minimum. From energy efficiency point of view it is best, as well as healthier, to use natural light whenever possible.
The application of modern lighting solutions can ensure adequate lighting of every single room depending on its purpose, which contributes not only to energy efficiency, but also health.Biggest energy savings are achieved by using the so-called "energy saving lamps". They use up to five times less energy and last about eight times longer than regular lamps. The classic lightbulb emits 95% of heat radiation and just 3-5% light radiation, while modern light sources emit 10, and sometimes more, efficiency as they are based on a different technology.
As technologies and our own living standards grow,so does the number of appliances we use on a daily basis. It is estimated that smaller appliances are responsible for up to 10% of overall electricity usage in a home. This is why it is advised to consider a particular device’s energy class, as well as to turn off everything when not used and also to avoid the “stand by” mode.
Almost 50% of all energy needs in a home falls to the heating system. When building sustainably we can achieve bigger savings in all energy types, particularly heat and electricity without lowering our comfort. This is why building sustainably is a key factor in modern housing.
More than ⅕ of electrical energy within a typical household is used for saving food. What we choose as a refrigerator and/or cooler is very important as those types of appliances are running 24 hours a day so how much they use up is immediately reflected in your budget and monthly expenses. In addition to keeping track of how much energy they use, it is also important to note how much volume you actually need, so keep in mind not to buy too small or too big of an appliance. In both freezers and refrigerators temperatures should be set to the optimal level (– 7 °C for refrigerators and – 18 °C for freezers) so that there is no need for extra energy to keep all of the food and beverage items fresh.
For energy rational and efficient use of dishwasher and washing machines it is important that they be optimally filled as well to use proper washing programs. Instead of using an electrical dryer, you can choose to air dry your laundry. The biggest part of electrical energy is used to heat up water and dry out clothes, so when you try to avoid unnecessary extra heating you can save up a lot of energy
In order to reduce energy consumption for electricity, particularly in terms of room cooling, it is advised to maintain an optimal room temperature. Those temperatures depend on the type of the room - for ex. 20 degrees Celsius for living room and classroom , while 24 degrees is recommended for bathrooms.
Fluorescent lightbulbs ("neon tubes") are made from a glass tube lined with phosphor. The tube contains inert gas with a very small amount of mercury. Fluorocompact lightbulbs are bent fluorescent tubes with an inert muffler.
LED lights are now being increasingly used as a substitute for a classic lightbulb, as they use up less energy and last longer than the bulbs that have a tungsten filament.
Day light reduces the need for using artificial lights and by doing so allows for significant energy savings. This is why it’s important to reduce the use of indoor lights and opt for daylight whenever possible. Apart from lowering our electricity bill, daylight is important for our health as well.
There are a lot of reasons why we should use sun energy as much as possible.
Kitchen has a lot of appliances that need a lot of energy and all of them are used daily. Apart from the dishwasher and the refrigerator, these large energy users also include the stove and kitchen hood. This is why we need to be mindful when purchasing those elements as by selecting appliances with a higher energy class, we can save a lot more.
One of the ways to use the stove rationally is to select a heating area that matches the size of the pot used – it shouldn't be larger, or smaller than the pot bottom. By doing so energy isn’t radiated around nor does it take longer to cook.
