The city of Helsinki opens the energy consumption data of its public buildings to application developers to become a carbon-neutral city

The city of Helsinki opens the energy consumption data of its public buildings to application developers to become a carbon-neutral city

96% of the city of Helsinki's carbon dioxide emissions come from the energy consumption in its public buildings.

How much electricity and district heat were consumed in a local school or library yesterday? The new Nuuka Open API, now open for testing, can now be used to retrieve hourly electricity and heat consumption data for approximately 1,700 service buildings in the City of Helsinki. The ambition is to accelerate Helsinki's journey towards becoming a carbon-neutral city.

"Helsinki schools, kindergartens, libraries, hospitals, and hospice buildings" list leading energy expert Veera Sevander, public buildings, whose energy consumption information is now available to anyone interested."

The new open interface service was presented to application developers at the Helsinki Loves Developers event in February 2020. The event brought together amateur coders and software companies in the city hall.

The city of Helsinki has been tracking the energy consumption of its buildings since the 1980s. With the carbon-neutral Helsinki 2035 program, consumption-monitoring has become an increasingly important tool. Veera Sevander reminded listeners at Helsinki Loves Developers that the heating of the public buildings alone will produce the lion's share, 56 percent, of Helsinki's greenhouse gas emissions. Far behind are both traffic and the use of electricity. "And a staggering 96% of the City Group's carbon dioxide emissions come from the energy consumption of its public properties. So, let's talk about this huge pot," Sevander says.

All buildings data accessible in one place

The city of Helsinki implemented the new Nuuka platform in spring 2019, for centralized monitoring of energy consumption and conditions in its public buildings. It makes all the information from the city's public buildings accessible in one platform. The system is already collecting energy consumption data on the building stock of the entire city and will soon also include water consumption and waste volumes. The system also collects data on the indoor conditions of buildings, such as temperature, carbon dioxide levels, volatile organic compounds, and fine particle concentrations. In a few buildings, the system also provides user satisfaction information.


The data is being utilized in many ways. System alarms help respond to problems detected in buildings, while accurate energy consumption information enables improvement of the energy efficiency in the buildings. "The ultimate goal, according to Sevander, is to turn urban properties into intelligent buildings whose HVAC systems are controlled, based on the real-time measurement and indoor climate information."

Olli Parkkonen, Head of business development at Nuuka Solutions, says that many property owners complain about challenges in accessing their data. "Information is in silos, scattered across different information systems. As a result, sharing information becomes difficult, as is utilizing it, Parkkonen describes. Helsinki's new real-time data platform makes the same information accessible to everyone involved, from building owners and users to maintenance."

The open data is already making a difference

The city of Helsinki has long been a pioneer in opening up public data in the towns to everyone. But, what can you do with the energy consumption information of buildings? The question was answered at the seminar by application developer Juha Yrjölä. The Yrjölä system harnesses the Nuuka Open API's hourly energy consumption data and combines it with weather data from the Finnish Meteorological Institute. Then, based on historical data, it simulates the size of an optimal solar power plant for each of the 1,700 service buildings in the city.

"The profitability of a solar photovoltaic investment is significantly affected by the property's electricity consumption, says Juha Yrjölä, the best investment for a rooftop solar power plant is in properties that have the highest electricity consumption during the day and especially during the light season."

In the workshop section of the Helsinki Loves Developers event, participants got to think about how to use the new API. The discussions were around, for example, combining weather data and consumption data from the Nuuka Open API.

On Sevander's wish list is to get as much user feedback as possible from the now released test version of the API and the data it contains. Based on this, the production version of the API will be built. When the final interface is released in the HRI data catalog in the spring, the interface builders can only wait for the excitement of what applications will emerge in the hands of skilled coders.

"I look forward to some interface user providing the city with something we did not even know that we wanted," says Veera Sevander, leading energy expert of the city of Helsinki. Application developers appraise the opening of public data repositories through APIs, as various web and mobile applications now can search the open interfaces for the data they need with specific queries, and for that, the information provided always will be up to date. 

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