The Explorer is a one-of-a-kind search engine that showcases profitable climate solutions from all over the world which are part of an ever-growing, curated, and publicly-accessible database. Select your profile, your needs and climate goals to discover the solutions that fit best with your situation.

Explore Learn more

Cancel Confirm

My Search Alerts

The Solutions Explorer lets you create alerts that match your needs. You can create several alerts and you will receive a notification each time a new Solar Impulse Efficient Solutions is labeled and matches your filters.

Your Search Alerts will show up here.

Sign in to create alerts for your filters and search terms.

Sign in

Don't have an account?

Sign up

My Favorites

The Solutions Explorer lets you shortlist your favorite solutions.

Your favorites will show up here.

Sign in to add a solution to your favorites.

Sign in

Don't have an account?

Sign up

Contact the Solution's Provider

You can contact each Solution’s Provider through the « Solutions Explorer » contact form. The team will also follow up to make sure you’ll have an answer to your request.

Your contact form will show up here.

Sign in to contact the Solution's Provider

Sign in

Don't have an account?

Sign up

My Account

Sign in

Don't have an account?

Sign up


A simple yet ecological shower drain with heat recovery

December 2020
Gallery Joulia-Twinline 1
Gallery Joulia-Twinline 1


The impressively simple Joulia-Twinline technology proves that there is another way. By means of an ingenious heat exchanger module, the heat energy of the used shower water is reused to warm the incoming cold water mains. Thanks to this technology, 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. By this simple means, a 4-person household can save about 1900 kWh per year. Joulia-Twinline is particularly performant in places where many people shower, such as sport centres, gyms, hotels or clinics. A single Joulia- Twinline can generate about as much heat energy as a 15m2 photovoltaic array would produce in one year (1'900 kWh/a). Showering with a clear conscience is thus both ecological and delightful. The sophisticated technology is concealed under a simple stainless steel cover. Because the heat exchanger cover also serves as a trap, the total installation height is comparable to conventional shower drains and can also be used in renovations. The technology is practically instant and cleaning is simple thanks to the easily-removable cover.

  • /
Label Date December 16, 2020
From Switzerland
Maturity stage Small scale commercialization
Looking For Network, New clients, Visibility, Partners, Credibility

The environmental benefits

  • The drain doesn't emit any CO2 in the atmosphere, doesn't use any electric energy, just works by water flow
  • Save as much energy as 15 m2 of solar panels would have produced, whilst showering
  • Joulia-Twinline wins up to 60% of the normally lost energy back
  • Joulia-Twinline can be recycled by almost 100%
  • No impact on health

The Financial benefits

  • Joulia-Twinline saves up to 60% of thermal energy with each warm shower
  • A 4-person household can recover arround 1'900 kWh per year

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.

View company profile Solution website
Headquarters 2503 Biel, Schweiz

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.

View partner profile
Solutions Associated 39


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.

View partner profile
Solutions Associated 65
Contact the Solution Provider Add to Favorites

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.