Tenant engagement: two solutions to avoid rebound effects in energy efficient refurbishment projects

How to ensure the effectiveness of energy efficient renovation projects in the long run? In the framework of the EU-GUGLE Smart City Initiative, the six pilot cities have bet on tenant engagement to maximise energy savings in their freshly renovated buildings. Currently, one of the main risks limiting the impact of energy efficiency renovation measures is the so-called rebound effect: after refurbishment, tenants might be tempted to heat more if they see their energy bills decreasing. Or if they do not understand how the new system and technologies work they might install extra equipment, consuming more energy.

Fortunately, new solutions exist today to actively involve tenants in the energy saving process and thus prevent these negative effects. The EU-GUGLE pilot cities Aachen (Germany) and Sestao (Spain) are leading the way.

Tailored advice and tools to foster good practices in Aachen

For the inhabitants of the Aachen North district, renovation rhymes with consultation and information. Not only were tenants invited to take part in dedicated meetings to discuss their needs and the upcoming refurbishment, they were also provided with a special ‘Energy Saving Box’. The box contained an ammeter to measure the consumption of their electrical devices in real time, two LED lamps, switchable multiway connectors, a thermometer for each room with a coloured scale of recommended temperatures, hygrometers to evaluate the humidity as well as multilingual brochures with energy saving tips and contact persons. In addition, innovation vouchers financed by the city services entitled tenants receiving social welfare to benefit from an expert visit to perform an ‘energy saving check’. For households living in the building, very often refugees or migrants, unused to European standard heating devices, these visits were the opportunity to receive specialised and dedicated guidance on their energy consumption. To further increase the social impact, unemployed people have been trained as energy consultants to perform these visits.


Sestao: Empowering users through real time control management systems

In Spain, one of the most common complaints from energy consumers is linked to the lack of monitoring of their actual consumption. As in many other countries, users receive an invoice after the end of the period, making it hard to control their energy expenditure. To address this concern, prepaid systems have been installed in newly refurbished apartments in Sestao, meaning households know in real time what their energy consumption and costs are. When the balance drops below €10, the user is warned through an alarm emitted by the monitoring device installed in their apartment. They can then top-up their balance via the monitoring device, online, or via a toll-free phone number. Several months after the installation, users show great satisfaction with the new devices and claim to be very happy to finally have control of their energy expenses.

“Education and real-time control are key to empower users over their electricity consumption, and, as a result, safeguard the success of energy efficient renovation projects”, says Florencio Manteca, Energy in Buildings Department Manager at CENER, Spain’s Renewable Energy Centre, and coordinator of the EU-GUGLE project. Taking this lesson into account, cities within the EU-GUGLE initiative have made tenant engagement an essential pillar of their activities, paving the way towards active citizen participation in the decarbonisation of the European building stock.