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Joulia-Inline & Joulia-Twinline

A showerdrain that reclaims up to 60% heat energy from used shower water by pre-warming the fresh cold water

October 2018
August 2022
  • /

Joulia-Inline & Joulia-Twinline by Joulia SA implemented by Freilager in Zurich (Switzerland) in 2022

Recovery rate of up to 42% of otherwise lost heat from the showers

Joulia-Inline & Joulia-Twinline by Joulia SA implemented by Gangloff Immobilien AG in Bern (Switzerland) in 2022

Taking into account the number of residents and the standard use of a shower, the energy savings in this building complex are 1 835 kWh per Joulia-Twinline system and 326 630 kWh in total.

Joulia-Inline & Joulia-Twinline

A showerdrain that reclaims up to 60% heat energy from used shower water by pre-warming the fresh cold water

  • World Alliance Member
  • Featured Solution
  • Labelled Solution
Label Date August 16, 2022
From Switzerland
Maturity stage TRL 9 / CRI 5-6 - Market competition driving widespread deployment &/"Bankable" grade asset class

Reclaim valuable heat energy from used shower water by pre-warming the fresh water before it arrives at the mixer. The shower drain Joulia has to be connected to the freshwater. By means of a heat exchanger module, the heat energy of the used shower water is reused to warm the incoming cold water mains. In this way, the cold water arrives at the mixing valve up to 20°C warmer than before (from 10°C up to 30°C). Therefore, substantially less hot water is needed. Joulia-Inline is sold with either 3 or 5 heat exchanger tubes, and Joulia-Twinline with 6 or 10 which you can select depending on whether maximum efficiency or minimal installation height is more important.

The Environmental Benefits

  • Thanks to the low building height the Solution can be placed in every shower floor and will work without any moving parts nor electricity
  • Save as much energy as 8 m2 (Joulia-Inline) or 15m2 (Joulia-Twinline) of solar panels would have to produce and this whilst showering
  • Certified for connection to drinking water in many European countries
  • The drain doesn't emit any CO2 in the atmosphere, doesn't use any electric energy, just works by water flow
  • Closing the last gap in the building envelop with Joulia shower drain channels with integrated heat exchangers

The Financial Benefits

  • Joulia saves up to 42% (Joulia-Inline) or 60% (Joulia-Twinline) of thermal energy
  • A 4-person household can recover around 1'000 kWh (Joulia-Inline) or 1'900 kWh (Joulia-Twinline) per year
  • The Joulia-showerdrain has a short payback time between 3 - 6 years (Joulia-Inline) or 1 to 8 years (Joulia-Twinline), depending on its usage and energy prices

Target client profile

Activity Region

  • Headquarters
  • Activity

Company Profile

Joulia SA

How can one shower in comfort while still saving energy? With Joulia, the shower drain with heat recovery.

Headquarters 2503 Biel, Schweiz
Type Company
View company profile Solution website

Networking Partner

The Enterprise Europe Network

The Enterprise Europe Network helps businesses innovate and grow on an international scale. It is the world’s largest support network for small and medium-sized enterprises (SMEs) with international ambitions.

Solutions Associated 39
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As an expert for the innovation scene in energy and environmental technologies, CleantechAlps (Sion, Switzerland) is a hub for the cleantech ecosystem, connecting its stakeholders with relevant partners.

Solutions Associated 65
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The Climate Innovators Network by Kite Insights & Leading Edge Only (LEO)

Solar Impulse has teamed up with Kite Insights and Leading Edge Only to bring together an exciting new global ecosystem for climate innovation, designed to scale industry-leading solutions: The Climate Innovators Network.

Solutions Associated 6
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The information set out above, is solely for the purposes of information and the Solar Impulse Foundation does not provide any guarantee as to its authenticity, completeness or accuracy. This information does not constitute investment advice or a recommendation to buy into, transact or to enter into any agreement with any of the parties or persons mentioned above. Potential investors or interested parties are solely responsible for their investment or business decisions and for performing any due diligence required by the circumstances. The innovator Joulia SA has asserted ownership of the intellectual property rights for images, videos, and content showcased above, affirming full and unrestricted usage rights, and has provided explicit permission for the Solar Impulse Foundation to publish such information designated as "public" in the application form.