Comparison of new and refurbished buildings: energy and technology

New houses often convince with a very high standard, while older buildings often need renovation in the area of energy and technology. Energy efficiency has a very high priority when building or renovating a house. For new buildings, there are regulations that every builder must comply with. For example, an energy-efficient heating system must be installed in combination with a solar thermal system. There are also requirements for the insulation of the exterior walls, the roof and the windows. In the context of a renovation, you can also comply with the specifications. There is currently no legal regulation for renovations. However, building owners benefit from significantly lower energy costs. Since the costs increase regularly, you will save a large part of the investment again over the years. In addition, you make an important contribution to the preservation of the environment.

Independence from the energy supplier

Many building owners would like to be largely independent of the energy supplier. They also like to avoid buying oil, especially since the tanks needed for oil heating take up valuable space in the basement or in an outbuilding. In addition, gas and oil heating systems are not counted as renewable energies. Heat pump heating systems are becoming increasingly popular. You can opt for air heat or geothermal heat.

Cost recovery through solar thermal system

Heat pump heating systems require electricity to operate. In many regions it is possible to extract geothermal heat. Air source heat pumps are installed as an alternative. The high energy costs required to operate the heat pump are covered in whole or in part by a solar thermal system. This is installed on the roof of the house or an outbuilding. The electricity is fed directly into the heating system and the energy circuit of the house.

Power surplus or resource shortage?

If more electricity is produced than necessary on bright days, this can be stored in a battery. If the solar power is not sufficient, the capacities in the battery are accessed. Only when these capacities are also exhausted is the service of a local or national supplier required. This means that you have to sign a contract. However, you only use this for a few weeks a year.

Solar thermal system and heat pump heating: an economical combination!

If you install a high-performance solar thermal system in combination with a high-quality battery, you can operate your heating system for most of the year without additional energy costs if you use energy sparingly. In addition, the combination of solar thermal system and heat pump heating meets high energy efficiency requirements. You use renewable energies and relieve the grid by producing and storing your own electricity.

Technical annex

The demands on the technical installations in houses and apartments have risen sharply in recent years. The possibilities of technical installations are very diverse. During a renovation, all electrical wiring should be replaced. New cabling for the installation of a network or for elements of the smart home system can be laid in cable ducts or under the floor. This makes it easier to install or expand components at a later date.

Commission a specialist to safeguard your system

When installing a technical system, protection is very important. This is especially true for powerful appliances such as the electric stove. The washing machine and dishwasher should also be installed safely. With these devices, water and electrics work together and under no circumstances should an electric shock occur. The design and installation of the fuses should be done by a professional. A main fuse is required to protect the entire electrical system. In addition, the circuits are provided with individual fuses.

Modern systems look better in the exposé

It is advisable to completely replace older security systems with new components. This not only serves the security, but also has a positive effect on the resale value of the house. Modern systems from the field of energy and technology find a special mention in the exposé and increase the purchase price for the property. Potential buyers are willing to pay a little more for a house that is technically up to date.

Further information on the subject of house building

Here you will find further information and tips on the subject of house building.

Building materials: concrete, wood, stone, glass and plastics

Building materials are indispensable for the new construction of a house, but also for the renovation. Materials such as wood, stone and concrete are predominantly used. But plasterboard, glass and various plastics are also used. Building owners can influence the type of building materials. Basically, it is important that you pay attention to high quality. It doesn’t matter whether you are overseeing the construction of a new house or opting for the renovation of an existing building. The building materials used are usually used for decades. They are exposed to a very high degree of stress, both on the outside and inside. When using building materials that have qualitative limitations, minor renovations are often necessary at short intervals. You can prevent this by selecting high-quality building materials.

• Click here for the article Building Materials.

Interior fittings for new buildings and renovations

The interior finishing of the house includes the design of the walls, ceilings and floors. In addition, the installation of the electrical systems, the heating and the water circuit takes place. Stairs and doors are installed and fixed fixtures are integrated in the kitchen and bathroom. When building a house, interior finishing takes about the same amount of time as the construction of the building up to the topping out ceremony. The interior fittings can be very individually designed by the builder. Not only with a new building, but also in the context of a reorganization a new planning of the interior fittings is possible. If an extensive renovation with a change in the internal structure of the house is planned, the house should be empty for the period of the construction work. Otherwise, the renovation will be difficult.

• Click here to go to the interior design article.

Photovoltaic system – the different variants of renewable energy generation

The system that is chosen by most is the so-called photovoltaic system that generates electricity with the help of solar energy. With such a system, the owners are independent of public grid providers and do not have to pay more for their own electricity. But also with the photovoltaic systems there are different variants, each of which has its advantages and disadvantages.

Feed-in system – earning money with your own electricity

The most commonly used variant of the photovoltaic system is the feed-in system. This produces electricity for the household and feeds the electricity that is not consumed into the public grid. As required by law, the house is connected to the public grid and feeds surplus electricity into it. For this, the Renewable Energy Sources Act (EEG) stipulates that the producer must be remunerated. The so-called feed-in tariff varies between 10 and 13 cents per kilowatt hour (kWh) depending on the nominal output of the system and is fixed for the next 20 years. To illustrate this: An average family consumes only about 30 % of the electricity generated. 70 % is fed into the public grid and remunerated. However, there is a trap here that private individuals often fall into, because selling electricity is a trade and as soon as a private individual does this, he becomes a freelancer and is self-employed. Taxes and lots of paperwork are just waiting for you. To avoid this, check out our guide on all things solar without the tax office! Through an electricity storage, the self-consumption can be increased up to 75% and the owner benefits twice from the electricity.

Advantages

• Reimbursement of sales tax on the purchase price of the plant
• Good price-performance ratio
• Feed-in tariff according to EEG as additional income

Disadvantages

• Registration of the plant as a trade
• Subject to the obligations of the EEG
• Increased bureaucracy

Such feed-in systems are particularly suitable for property owners who have a constant average electricity consumption and want to drastically reduce electricity costs. On the contrary, such a plant can not only reduce annual electricity costs, but also be used as a source of income.

Zero feed system – all the electricity for your own home

The second variant of the photovoltaic system is the so-called zero feed system. As the name suggests, no surplus electricity is fed into the public grid. In the best case, 100% of the electricity produced is consumed in one’s own household, so that nothing is fed into the public grid. In order to ensure this, the system must be precisely adapted to the individual needs of the owner and also have a suitable electricity storage system. The electricity production is additionally controlled by an inverter, so that the output of the system exactly matches the electricity consumed and no electricity is fed into the public grid. The owners of such a system thus forego the feed-in tariff under the Renewable Energy Sources Act (EEG), but at the same time they avoid all the obligations that the feed-in tariff entails. You do not have to register a business and you do not have to pay taxes for the electricity fed into the grid. Although the photovoltaic system is intended to generate 100% of the electricity required, the property is still connected to the public grid so that it can continue to draw normal electricity if the solar power is not enough.

Advantages

• No increased bureaucratic effort, such as business registration, etc.
• Greater independence
• No obligations under the EEG

Disadvantages

• No feed-in tariff
• No refund of sales tax

The zero-emission system is therefore particularly suitable for private individuals who have a high energy consumption. The installation of a suitable electricity storage unit is mandatory for such a system, so that the self-produced electricity can be used most effectively.

Photovoltaic island system – independent of the public power grid

The photovoltaic stand-alone system variant does without the connection to the public grid and assumes that the solar system can always supply the electricity storage system with energy. The household is therefore supplied with electricity solely from the solar modules and does not rely on electricity from the public grid in an emergency. The owner is therefore not dependent on electricity from the public grid at any time. Here we will first distinguish between two types.

Stand-alone system without mains connection

As the name suggests, this model is a system that is not connected to the public grid in any way. The house relies exclusively on energy from the photovoltaic system. The system was designed for such a case so that both solar modules and energy storage are so large that they can independently supply the entire house with electricity without resorting to another power source. The electricity in such a house is therefore produced and stored 100% by the photovoltaic system. However, this system is usually only installed when a connection to the public power grid would be too costly. This is particularly the case for remote houses, mountain huts or individual infrastructures.

Island system for backup power

Independence from public electricity can also be made possible for German homeowners. The installation of an island system for emergency power is the solution here. In the event of a failure of the power grid, the stand-alone system for emergency power can then intervene. It makes it possible for both feed-in and zero feed-in systems to become an island system in an emergency. In the event of a power failure of the public grid, this system switches to backup power within a few seconds and the house remains normally supplied with electricity. So, the household is not dependent on the public grid and does not have to worry about a power outage. Here it is ensured that there is always enough power available. During installation, the entire house is disconnected from the public grid and a backup power system is set up that can communicate with the storage system.

Advantages

• Function as a backup power system
• Maximum independence from the public power grid
• Protection against power failures

Disadvantages

• Significant additional costs
• Is rarely used
• There is hardly any economic benefit for the owners

Such an investment does not always make economic sense for the homeowner. So before you decide on this option, first check your average daily consumption, the appropriate size of the system and the design of the solar storage tank. With this, you can calculate whether an investment would be profitable for you or not. The independence that owners have with such technology from the public grid is undisputed and will change and influence the energy policy of Germany in the coming years.