Kora Green City, one of the most efficient accommodations in the world

Passivhaus Certification. PassivWHAT?

The German Passivhaus standard is a rigorous, voluntary certification that evaluates various construction parameters, such as bioclimatic architecture, complete thermal insulation, and mechanical ventilation with heat recovery.

In other words… The Passivhaus certification ensures that our buildings are highly efficient, with nearly zero energy consumption and excellent indoor air quality. All of this guarantees maximum comfort, allowing our guests to rest and feel at home.

Energy Efficiency: Saving 75% on Energy

Staying at Kora Green City means saving 75% on energy compared to newly constructed buildings that do not have Passivhaus certification. Can you imagine paying only 25% of your energy bill?

This energy-saving figure for Kora Green City is based on the reference value published by the German Passive House Institute for constructions certified under its sustainability and energy efficiency criteria.

Environmental Awareness: Avoiding 314 Tons of CO₂ Emissions Annually

Every year, Kora Green City prevents 314,006.42 kg of CO₂ emissions from being released into the atmosphere—equivalent to approximately 865 kg per day. This achievement is the result of combining the original building’s energy-efficient construction with the continuous improvement of our facilities.

The calculation of avoided CO₂ emissions is based on the building’s energy efficiency certificate, taking into account its usable living area of 7,069.40 m² and the electric mix factor of 0.260 kg CO₂ e/kWh—an official value provided by the Ministry for the Ecological Transition and Demographic Challenge in 2023. Additionally, the 75% energy savings achieved through the Passivhaus certification significantly contribute to reducing CO₂ emissions.

Equivalent to the CO₂ Absorbed by 682 Trees Over 20 Years

What do Kora Green City’s sustainable efforts amount to?

We minimize our carbon footprint by preventing the release of 314 tons of CO₂ annually—equivalent to the CO₂ absorption work that 682 pine trees would do over 20 years.

For this calculation, we used the radiata pine tree as a reference, the primary species in the forests that cover the Basque Country. This tree occupies 35% of the Basque Country’s total forest area and has a 35-year felling cycle. Over its lifetime, a radiata pine can absorb an average of 1.56 tons of CO₂.

Over its lifetime, a radiata pine can absorb an average of 1.56 tons of CO₂.

How Do We Achieve This?

Natural Resources: 100% Green Energy

All the energy used at Kora Green City comes with a Guarantee of Origin, certifying that our energy consumption is 100% renewable. This means our guests can enjoy their stay knowing their energy use does not contribute to climate change.

Is it your first time hearing about Guarantee of Origin? It’s a certification that ensures the electricity you receive is generated from renewable sources or high-efficiency cogeneration. And yes, you can also opt for it in your home to consume 100% green energy!

Hello Sunshine: 58 Solar Panels

In 2022, Kora Green City started with 26 solar panels. But that wasn’t enough for us… so we added 32 more! We now have a photovoltaic system of 58 solar panels covering 140 m² on our Greenfinity Rooftop, producing 27,000 kWh of solar energy annually.

Where does this energy go? We use it to power the building’s aerothermal system. Keep reading!

Aerothermal Technology: A Building Without Boilers

At Kora Green City, we heat the water for your shower through heat exchange between indoor and outdoor air using a high-efficiency heat pump.

Long live a boiler-free life!

Geothermal Energy: 18 Boreholes, 150m Deep

We have 18 boreholes, each 150 meters deep, that allow us to produce geothermal energy. Using the Earth’s internal energy, we can heat or cool the water that circulates through the underfloor heating systems in the 180 apartments at Kora Green City.

And More Measures for Better Energy Savings:

1. Elevators that generate their own energy.
2. Triple-glazed thermal insulation.
3. Paperless policies and local sourcing (km0).
4. Eco-friendly, refillable, and vegan amenities.
5. No plastic is fantastic. Single-use bottles are long gone.

At Kora Green City, we are committed to sustainability and energy efficiency, striving to provide our guests with a unique, environmentally friendly experience. Thank you for being part of this journey toward a greener future!