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LIMITED QUANTITIES, BE HURRY – HEAT PUMPS AT DISCOUNT PRICES!
LIMITED QUANTITIES, BE HURRY – HEAT PUMPS AT DISCOUNT PRICES!
In our previous guide, we delved into for heat recovery (LTO) – a critical technology that prevents warm air and energy from escaping to the magpies. We said it’s absurd to waste heat that’s already been produced. But what if we could take this idea even further? What if we didn’t just transfer heat to the supply air, but took that wasted energy and actively refined it into the most valuable assets of a property: hot water and underfloor heating?
This is the idea around which exhaust air heat pump (PILP) is designed. It is not just a ventilation unit, but a comprehensive building technology heart that combines mechanical ventilation, advanced heat recovery and efficient heat pump technology into one intelligent package. It is the ultimate answer to the challenges of a modern, energy-efficient home.
This article is a guide for those of you who live in or are building a new generation property and want to understand how to turn wasted energy into a valuable asset.
Expert perspective: This article was written by Jukka Poikela, Renewe's leading pilp expert. He specializes in comprehensive energy systems for modern, energy-efficient properties and, with over 15 years of experience, knows how to squeeze every last bit of benefit out of a property's energy cycle with PILP technology.
An exhaust air heat pump is not a universal solution for all buildings, but a specialized tool designed to excel in a specific environment. Its efficiency is based on the fact that the building's heating needs are initially low and ventilation is mechanical.
PILP is definitely at its best in very well-insulated detached houses, semi-detached houses and townhouses that are new or built in recent years. In these low-energy properties, the heating energy requirement is so low that PILP can often cover it completely, while also producing all the hot water. It is a space-saving and cost-effective overall solution that handles three building services areas at once.
However, it is important to understand its limitations. In older and more energy-consuming houses, the heating capacity of PILP alone is often not enough. The energy it produces is directly linked to the amount of ventilation, and it cannot compete in the efficiency class with, for example, geothermal In these locations, it can function as part of a hybrid system, but a more efficient solution is needed as the main heat source.
System architecture in plain language, one machine handles ventilation, heat recovery and heat pump; domestic water heating is usually a priority and the heating circuit is supplied when the set temperature of the tank is full. In small water-circulated underfloor heating, a small buffer volume is often needed to keep the compressor operating cycles reasonable; in severe frosts, the built-in electric heater ensures the supply of heat and domestic water.
By investing in an exhaust air heat pump, you are not just purchasing an air conditioning unit, but a complete heating and hot water system. Although the purchase price of the device is higher than that of a traditional LTO unit, it replaces the need for a separate hot water heater and, to a large extent, also for the rest of the main heating system.
When looking at the total costs of an entire building project or energy renovation, PILP is often a very competitive and sensible choice for the right type of property. It simplifies building services, saves space and produces significant savings in annual energy costs. Naturally, the installation work is also eligible for household deductions for consumers, -35%.
For housing companies, PILP investment is often particularly interesting, as it improves the energy rating of the entire property and increases the market value of the apartments. In addition, housing companies can benefit from various energy renovation subsidies and grants.
Although PILP is primarily known as a solution for single-family homes, it is also excellent for the needs of housing associations and small commercial buildings. In terraced housing associations and small apartment buildings, PILP systems can serve several apartments centrally, which further improves energy efficiency.
In apartment buildings and commercial buildings, an exhaust air heat pump can be implemented as a centralized solution, where the energy from the exhaust ducts is used for domestic water and heating; the combination of LTO + exhaust air heat pump reduces the need for district heating or electric heaters, and demand control together with zoning reduces both energy use and power peaks; reporting is integrated into building automation and ESG/CSRD metering.
For housing companies PILP offers specific benefits: It significantly reduces the company's energy costs, improves indoor air quality throughout the property, and increases the value of the apartments. In addition, the centralized system is easier to maintain and monitor than individual apartment-specific solutions.
In commercial buildings, such as offices, nursing homes or daycare centers, the ability of PILP to produce plenty of hot water makes it a particularly attractive option. In these locations, hot water consumption is often high, and PILP can optimally utilize the building's high ventilation volume.
Renewe's experts will assist you in all phases of the project – from thorough mapping and planning to professional installation and maintenance.
Book a free survey: 010 660 3030 | info@renewe.fi | Fill out the form online
Is PILP sufficient as the sole heat source in winter? In modern, well-insulated, low-energy buildings, yes, it is usually enough. However, all PILP devices have a built-in electric heater that automatically switches on to help in the worst frosts to ensure that there is enough heat and hot water in all situations.
Is PILP suitable for a housing company or a commercial building? Yes, especially for terraced houses, small apartment buildings and small commercial buildings. In larger projects, multiple PILP units can be installed or combined with other heat sources. For housing companies, PILP offers a centralized, energy-efficient solution that reduces shared costs and improves living comfort.
How much energy does PILP save compared to direct electric heating? In an energy-efficient new building with water-circulating underfloor heating, PILP can save up to 50–60 % of total energy consumption compared to a system with a traditional LTO machine and heating and hot water produced directly with electricity.
Can an exhaust air heat pump also cool? Yes, many modern PILP models can be equipped with a cooling feature. Cooling can be achieved either by connecting a separate ground cooling or cooling unit to the device, which cools the supply air during the summer heat. This is an effective way to improve living comfort all year round.
How much does PILP really save on a new detached house? Let's consider a modern, newly built 200 square meter detached house. The house is well insulated and has water-circulated underfloor heating. Its annual need for heating and hot water energy has been calculated to be approximately 17,000 kWh. We use the total price of electricity including transmission, €0.14/kWh, in the calculation.
1. Traditional solution
If a traditional, high-quality heat recovery unit (HTO) were installed in the house and heating and hot water were produced directly with electricity, the entire 17,000 kWh energy requirement would be purchased from the electricity grid.
The annual cost would be: 17,000 kWh * 0.14 €/kWh = 2,380 €.
2. Intelligent PILP solution
Let's take the same house, but equip it with a modern exhaust air heat pump (PILP). It takes care of ventilation, heating and domestic hot water. The PILP utilizes the energy in the exhaust air and produces the required 17,000 kWh of thermal energy with an average annual coefficient of performance (SCOP) of 3.0.
The new need for purchased electricity is now: 17,000 kWh / 3.0 = approximately 5670 kWh.
The new annual cost is: 5670 kWh * 0.14 €/kWh = approximately 794 €.
Summary: The annual savings are therefore: €2,380 – €794 = €1,586.
