Heating without gas or oil - with wood or a heat pump

Efficient heating is good for the environment and for your wallet. But which heating technology should you choose, what do you have to look out for during planning and how do you get subsidies or climate bonuses?

Away from gas or oil! That's what many property owners want at the moment. They all ask themselves the same questions - and answering them is not always easy. To shed some light on the subject, the editorial team asked Marco Bichsel, Marketing Manager Domestic at Schmid AG, energy solutions. The Eschlik-based company supplies installers from the region, advises builders and property owners, and produces and sells both wood and heat pump heating systems.

Mr. Bichsel, what are the basic reasons for renovating a heating system?

Marco Bichsel: "First and foremost is greater efficiency, i.e. lower heating costs. But also more environmental friendliness thanks to lower emissions, CO2 neutrality, greater reliability and, last but not least, legal regulations that oblige people to switch to more environmentally friendly technologies when replacing old night storage and oil heating systems are the main drivers of the current development."

Schmid AG has been developing and producing wood heating systems since 1936. What advantages does wood offer as an energy source?

"Firstly, wood is a locally available energy source, which provides a high level of supply security and good price stability. Secondly, wood is CO2-neutral, sustainable and particularly climate-friendly. Thirdly, modern wood heating systems work very cleanly and efficiently, regardless of whether they are fueled with pellets, wood chips or logs. Fourthly, wood heating systems are almost infinitely scalable. They are therefore suitable for single-family homes as well as multi-family homes, agricultural/forestry operations and commercial/public buildings. For example, we supplied the biomass boiler technology for a plant at the Nippon Steel Company, which has an output of 3.2 megawatts. By comparison, a pellet heating system for a single-family home has an output of around 15 to 50 kW."

Schmid AG has also been selling heat pumps from the manufacturer Nibe for two years. What are the current arguments in favor of heat pump heating?

" Air-to-water heat pumps in particular are quick and easy to install - and are basically the only sensible option for buildings that do not have Stack , for example because they were planned for night storage heating. Solutions with a ground-source heat pump are more expensive, but also more efficient at low outdoor temperatures. Depending on the accessibility, location, size and heating type - radiators or underfloor heating - of the property, one or the other is the better option. In addition, heat pumps are low-maintenance, durable, quiet and inexpensive to operate - as long as electricity prices are right."

You just mentioned the Stack in the house: What other requirements must be met for a wood pellet heating system?

"A dry storage room or silo is needed for the pellet store - as close as possible to the access road for the pellet delivery truck, at least 4^{m2 in} size and no further than 25 meters from the heating room, which must be at least 6^{m2 in} size. Sounds complicated, perhaps - but usually the existing oil tank room meets all the criteria for a pellet store. It is also important that the Stack is insensitive to moisture - thanks to chrome steel or ceramic inner pipe.

It also makes sense in most cases to have a buffer storage tank and depending on the boiler design and its size, an energy storage system is also necessary."

What to look for in wood heating and its technology and equipment?

"On good quality and modern, durable technology, as well as optimal suitability for the individual requirements and conditions of the corresponding building.

This absolutely requires serious advice and knowledge of the current systems. Today's pellet heating systems are versatile. Thanks to intelligent heating circuit management, they are suitable for several heating circuits, are available with solar thermal function, can partly also utilize moist fuels and much more. In addition, they can be combined with each other. For example, the pellet heating system automatically takes over when the log heating system has not been refilled - and also automatically shuts down again as soon as the log heating system has been refilled. This means that heat is always guaranteed - even if it's vacation time or refilling was not possible or was simply forgotten."

What is important in a heat pump?

"Here, too, quality, modern technology, reliability and correct calculation of output are the top priorities. Also very important is intelligent control, because only in this way can achieve maximum efficiency. Ideally, heat pumps are combined with floor heating systems. Radiator heating systems require higher flow temperatures - and this is where many heat pumps, especially air/water variants, reach their limits. In addition, depending on the installation site, it is important that the heat pump is very quiet. Otherwise, there may be problems due to noise emissions."

That sounds complex. How can laypeople find the right solution in such a wide range?

"Only on the basis of competent advice from an experienced, reputable installer, from us as a neutral manufacturer, and from specialized institutions such as the cantonal energy consulting service.

It's good to know that we have both wood heaters and heat pumps on display in our showroom. So people can get a live impression - and see, among other things, how compact modern wood pellet and log heating systems, but also heat pumps, are designed.

One thing is clear: every new building and every heating system renovation requires comprehensive, individually tailored planning. A heating system is cost-intensive and is operated for many years. This means years of accumulating additional costs with poor efficiency - and years of increasing savings with optimal efficiency. Therefore, it always pays to invest enough time in planning and calculating the heating system and to get the right partners on board."

Speaking of costs: The replacement of a heating system is supported with subsidies. How do you find out how much funding you are entitled to - and how do you apply for it?

"Subsidies are generally available when a gas or oil heating system is replaced with wood heating or a heat pump. However, there are pitfalls that you have to be aware of. For example, the canton of Thurgau calculates the subsidy for heating system replacement differently than Energie Zukunft Schweiz. In addition, Energie Zukunft Schweiz also subsidizes heating systems in non-residential areas, such as office or administrative buildings. This means that it is imperative to compare exactly where you will receive how much money. In addition, the application must be submitted correctly and in good time - before the heating system is ordered or even installed.

Ultimately, the same applies here: Laypersons are dependent on competent, neutral advice from installers, suppliers and manufacturers - and should also inform themselves on the relevant Internet portals of the Thurgau Energy Advisory Service, the Cantonal Energy Department and institutions such as Energie Zukunft Schweiz and read up on the subject. In this way, a well-founded decision can be made as to which type of heating - wood or heat pump - is most suitable for the respective new building, conversion or renovation project.
is best suited for the respective new construction, conversion or renovation project, how much power it must have and which features are necessary." Jörg Rothweiler

More information

can be obtained from regional heating installers, from Schmid AG, energy solutions (www.schmid-energy.ch), from the cantonal energy department (www.energie.tg.ch) and from the cantonal energy advice center (www.eteam-tg.ch).