The key solutions for the greenest buildings start with a precise energy audit of the building, developed by engineers at the initial design stage. What solutions can be achieved with this? – If we have the balance sheet and all the energy analyses, we can plan precisely, for example, systems that recover condensation heat, i.e. producing cold for the building while transferring heat to other consumers. And this is only the beginning of a long list of possibilities,’ argues Marcin Kosieniak, whose team is involved in the HVAC design of the most modern green buildings and office buildings currently under construction in Poland.
No one today doubts that EU regulatory pressure has forced the real estate market to make revolutionary changes in its approach to solutions that are expected to significantly reduce CO2. Energy savings also mean real financial savings – which is why investors are also looking closely at sustainable solutions.
“The calculation is simple. Better energy performance of a building translates into lower bills and a significantly higher valuation of the property in question. This is why certificates confirming the green aspects of buildings have started to play such a huge role in the commercial property market. In the industry, we have no doubt that their importance will grow. In addition, there is a kind of competition among real estate developers for the most environmentally friendly solutions. This is where cooperation with HVAC specialists at the design stage proves crucial, because being eco today is all about precision and detail,” explains Kosieniak.
Energy balance key to eco solutions.
The expert points out that for the industry – but also for investors or in the process of obtaining certification – the most important issue today in terms of green buildings is the properly implemented requirements for building operation.
“Without a well-prepared energy audit, it is impossible – I am convinced of this – to come up with any effective green solutions. A precisely calculated building not only uses less heat, it also uses less electricity. The same applies to cooling requirements. Less cooling demand means less electricity used to drive chillers, circulation pumps, valves and other such components. For this, a considerable amount of energy analysis is required,” says Marcin Kosieniak, co-owner of the design office PM Projekt, whose company is involved in planning and designing solutions in buildings and investments obtaining the highest certificates.
What is a property energy audit? It is a forecast of the amount of heat gain and loss that a building will have. The difference between these values shows how much thermal energy needs to be supplied to the building in order to keep it comfortable.
The energy balance developed at the design stage determines the subsequent decisions related to the solutions that determine how energy-efficient a property will be operated.
What do the greenest buildings have?
So, what solutions can be designed into HVAC solutions – with precise energy analyses?
– If I were to use an example of the most advanced solutions we design, I would start with something illustrative – like the fact that we use variable airflow controllers to adjust the amount of supply and extract air from rooms based on CO2 or other room presence sensors. This ensures that the ventilation systems work when people are in the rooms, which is exactly when ventilation is needed there. So there are no rigidly set schedules. Importantly for the overall project, we design and use systems that recover condensation heat, i.e. while producing cooling for the building, they simultaneously transfer the heat to other consumers. These other consumers are, for example, domestic hot water systems or secondary air heating systems. We recover heat from the exhaust air in the air handling units,’ Kosieniak enumerates.
Listing further solutions in this type of modern eco building, Marcin Kosieniak points out: We direct the exhaust air from clean rooms such as offices, conference rooms, lobbies, etc. into the garage instead of outside. – In one such project involving us, we heated the garage in this way without any heating equipment (!),’ he adds.
Heat pumps that work in the transitional period and in the cold period switch off in favour of heat from the hub.
Rainwater is recovered and then directed to flush the toilets.
“The premium high-rise we are currently working on is additionally equipped with photovoltaic cells and control algorithms set to minimise energy consumption. Of the building solutions, we use facades with the lowest possible heat transfer coefficients. In addition, we use a solar absorption coefficient of 0.30 for the glazing in summer, which is really a very low value on the market. The well-planned placement of plants is not without significance. Wellbeing is also one of the elements playing an important role in eco-design today,” adds Marcin Kosieniak, co-owner of the design office PM Projekt.
The number of certified areas of newly constructed buildings is increasing year by year. According to a recent report by the Polish Green Building Council, less than 40 million square metres of space are already certified in Poland.
On the Polish real estate market, there are five green building certification systems: the British BREEAM certificate, the American LEED, the French HQE, the German DGNB or the WELL certificate, which is focused more on man himself, on his well-being in the building. They all focus on pro-environmental aspects, such as the energy efficiency of the building or water management, and on creating a friendly working environment.
