Green-Y is the Startup of the Week 47: Affordable, Clean & Efficient Energy Storage System

Energy Efficiency and Environment, Energy Storage, Energy Supply

The issue of green energy poses two major challenges: The storage of energy from green energy and the question of heat/cold generation. In the ideal world, this is achieved with a single device. For some, this may sound like a high cost and energy expenditure. Our Startup of the Week Green-Y uses the well-known compressed air storage technology and solves the above-mentioned problems, in an efficient and sustainable way. Dominik Schnarwiler, co-founder of Green-Y, tells us more about the technology in today’s interview.

Hello Dominik! Great, that you are here today. To get you started, why don’t you tell us what Green-Y does? 

Green-Y combines electricity storage and heating/cooling in one device. This is reducing costs and emissions from buildings.

An important mission. How exactly do you make this possible?

We base Green-Y on patented air reservoir technology. There are two main processes: The charging and discharging of the accumulator. When charging, we compress air, which requires electricity and generates heat. The compressed air is then temporarily stored in compressed air tanks.

When we unload, the air from the compressed air tanks expands again at a later stage, which recovers electricity and generates cold at the same time. Thus, it is combining electricity, heat, and cold in one device.

In principle, one knows this technology for a long time, which allows us to reduce risks, complexity, and costs by using standard components. Yet, the technology has now been decisively developed further and the energy density is increased by a factor of 3, doubling the efficiency of heating and cooling. As a result, Green-Y can be used to heat and cool efficiently in a decentralized manner, i.e. directly in the building, which in turn makes its use as an electricity storage device cheaper.

Green-Y can be used in buildings and industries where there is a need for electricity storage, heating and/or cooling. Typically, Green-Y optimizes the use of electricity from the grid and the internal consumption of e.g. photovoltaic electricity, heats rooms and hot water, and cools rooms and servers.

What is the unique selling point of Green-Y?

Green-Y is environmentally friendly and profitable. The customers benefit as follows:

  • The profit is increased by reducing energy costs, which results in low amortization periods.
  • We can reduce emissions by replacing fossil fuels and integrating renewable energies.
  • Green-Y is environmentally friendly and recyclable, as only air and water are used as working materials.

Compared to competing products, the battery and heat pump, Green-Y is more than 5 times cheaper and does not generate any environmentally harmful waste. The latter is mainly produced by the limited resources of lithium and cobalt in the battery and by the environmentally harmful refrigerants in the heat pump. Thus the combined approach brings the unique selling propositions that clearly set us apart from the competition.

How do you integrate your product into a lucrative business model?

Our business model is initially based on a one-off sales margin, supported by a recurring share of maintenance and repair. In the future, we plan to introduce other business models, such as a contracting model with the end customer, which will cut the high acquisition costs for the customer and result in attractive recurring revenues for us.

Initially, we are approaching the end customer directly with the first installations B2C. In doing so, we take the first step into the market and aim for a product/market fit. After that, the aim is to address the so-called multipliers as quickly as possible. In doing so, the device or a B2B license is sold to e.g. energy suppliers or heat pump manufacturers. This allows us to scale quickly and efficiently.

You have already briefly touched on your target group. Could you elaborate on this topic further?

Of course. The technology is scalable from small applications in the single-family home sector to medium-sized applications in trade and industry and large applications centrally at an energy supplier.

In the beginning, we are clearly focusing on medium-sized applications in the commercial and industrial sectors. The first two customer projects were secured in a Swiss office building. An ideal application was identified there for market entry.

The niche market for office buildings in Switzerland already represents an annual market volume of over CHF 200 million. After the first projects have been realized nationally, we are quickly aiming for the DACH sector before we also want to operate throughout Europe and intercontinental.

This all sounds like very exciting developments. Where do you stand now?

The patented technology is validated on a prototype in a laboratory environment. We were also able to secure our first two customer projects. The next big step is the realization of the pilot project at a customer’s site. Installation in the Swiss office building will start in 2021. After that, we plan to install the first commercial devices in early 2022. For this purpose, we are currently looking for 2-3 further customer projects.

At the same time, we were able to conclude a successful seed investment round in summer 2020. This secures our financing up to and including the pilot project. We plan a Series A financing round for the end of 2021 to enable the commercialization of the product.

We are currently looking for new team members and investors for the next investor round. Also, we want new strategic partners for market entry, and customer projects for early 2022. Are you interested? Contact us and join the journey into a green energy future!


Dominik, thank you very much for the exciting conversation! We wish Green-Y every success for the pilot projects and the search for investors. 

If you would like to learn more about Green-Y, you will find more interesting information on Green-Y’s profile in our innovation network.

Startups of the Month – April 2020

Energy Efficiency and Environment, Energy Storage, IT & ICT

Our four Startups of the Week in April at a glance

In April, the startups Wecreation, IoT connctd, Qarnot and Ice on Battery gave us exciting insights into their solutions and innovations with their Startup of the Week interviews. We have compiled statements about their business models, markets, target groups and solution approaches for you here shortly. You can read the details in the individual interviews. If you want to contact them directly , feel free to use the messenger function in our database. There you can also present yourself with your own profile and get in contact with the startups.

WeCreation – Focus on the human part of digitalization (CW15)

“We empower organizations to actively shape the future through cultural change and future competencies and to use change as an opportunity.” Christian Binninger, Co-Founder Wecreation GmbH

Digitisation is not only being pushed forward technically. Rather, people are directly involved. This is why the start-up company WeCreation focuses on “the human part of digitisation”. Through agile projects, in various workshop formats or through leadership and team coaching, they accompany organisations in their transformation processes from within. This involves developing creativity, learning processes, teamwork and the acquisition of future skills. With their WeAcademy, people can deepen what the’ve been learning in the form of “blended learning”. In the wake of the Corona crisis, WeCreation has launched three new online formats. All organisations can benefit from their service offerings. Since its founding, WeCreation has focused on the energy industry and has worked closely with municipal utilities and utility companies. Its customers include the Haldensleben municipal utilities, the Menden municipal utilities and the Dessau municipal utilities. You can read more details about them and their services in the interview or find out more in their customer requests.

To the Startup of the Week interview CW15

IoT connctd – IoT platform for scalable data-based services (CW16)

“We designed and implemented the open and scalable Service Creation IoT platform to simplify the development of data-based services.” Axel Schüßler, Co-Founder and CEO of IoT connctd

IoT connctd has created a service platform for the use and application of IoT data. This helps customers to develop data-based scalable services. IoT connctd supports the technical implementation, such as data generation and evaluation, as well as agile further processing through simulations, tests, pilots and finally scaling. Their cloud-based IoT service platform maps the individual steps. The Startup addresses its offer to device manufacturers in the form of software. They can use the IoT platform as IoT backend. For service developers there is the GRAPH API, which works like a Google search engine for the Internet of Things. Here, IoT connctd takes care of the decoupling of user data and IoT data. They encrypt all interactions and allow only authenticated access. Hosting is provided in Germany and the EU. IoT connctd has a broad range of services on offer. They are also establishing a data marketplace to organise the targeted exchange of data. Their service offers around the IoT platform can be accessed worldwide. In contrast, they are currently focusing their projects on the European market. Further information, contact details as well as requests for partnership can be found in their requests in our database.

To the Startup of the Week interview CW16

Qarnot Energy – Patented Green IT approach uses waste heat from IT calculations (CW17)

“We use waste heat from IT calculations to heat buildings and water sustainably.” Paul Benoit, Co-Founder and CEO

With the increased use of modern IT technologies in the course of digitalisation, energy consumption is also rising. The provision of computing capacity in data centers is thus accompanied by increased energy requirements. At the same time, data centres generate a high amount of waste heat. Qarnot Energy has developed a solution approach. They make sensible use of the waste heat generated by data centres. This works by making it available to the energy system again through their patented technology. For this purpose, they have developed a computer heater and a digital water boiler. With these, they supply heating-customers with heat and computing-customers with computing power. Connections to the fibre optic network ensure an effective distribution in buildings with IT resources and heat. Their sales activities are focused on the B2B sector. Most customers are located in France. However, Qarnot Energy intends to extend its range of products to the European market, with a particular focus on the UK, the DACH region and Northern Europe. By recovering waste heat as a resource, Qarnot Energy can both reduce energy consumption and contribute to a significantly reduced carbon footprint of computers. Its worldwide patented technology enables an innovative, sustainable and economical Green IT approach that creates a node between IT and buildings. To contact Qarnot Energy directly, you can use our database and its requests.

To the Startup of the Week interview CW17

ICE-ON Battery – storing energy in cold (CW18)

 “We are working on an innovative cold energy storage system. The technology is patented and allows to store excess energy and reduce greenhouse gases.” Dariusz Ziemski, CEO

ICE-ON Battery uses ice as an energy source to store energy in the form of cold. Cold in turn is needed for industrial cooling processes or for air conditioning systems. With ICE-ON Battery, both conventionally produced and renewable energy can be stored in the form of ice. Heat is released when cold is converted into electricity. A combination of these two creates the conditions for an optimized use of energy in an energy multi-system. In combination with photovoltaics or wind, the efficiency of renewable energy can be increased and at the same time the energy efficiency of cooling and heating systems can be improved. This brings economic advantages and simultaneously reduces greenhouse gas emissions. ICE-ON offers its cold storage systems to system providers and companies in the renewable energy sector. They also work with industry associations, research institutes and governmental organisations. The first pilot projects are currently being launched in Germany. ICE-ON Batteries offers its customers a comprehensive range of services, including planning and concept studies, installation, maintenance and training. There will also be software solutions for remote control. Have a look at the database to learn more about their cooperation request.

To the Startup of the Week interview CW18

ICE-ON Battery is the Startup of the Week 18: Converting energy into ice

Energy & Environment, Energy Efficiency and Environment, Energy Storage

What if one could use the phase transition from water to ice? For example for energy storage? Our Startup of the Week has developed a product that enables energy storage and energy release with these phase transitions. The idea of ICE-ON Battery is not only innovative, but also good for the environment. In the interview CEO Dariusz Ziemski gave us more information.

Hello, Dariusz! Nice of you to answer our questions today. Why don’t you tell us briefly what the project ICE-ON is all about?

At ICE-ON Battery we are working on an innovative cold energy storage system. The technology has a patent and allows to store excess energy and reduce greenhouse gases.

What technology is behind it?

The ICE-ON cold energy storage system uses the phase transition from water to ice to generate energy. Basically, ice is the energy source in the ICE-ON battery. The energy is released in the form of cold, which is used in air conditioning systems or in industrial cooling processes. The ICE-ON Battery also offers a unique possibility to store electrical energy from conventional and renewable energy sources. During preriods of energy surplus we store this as ice.

The conversion of electrical energy into cold generated large amounts of heat. Depending on the solution, this heat is either lost or actually used. In combination with a remote control program, we enable optimal management and use of the stored energy. This functionality of ICE-ON offers unlimited application possibilities. On the one hand in cooperation with air conditioning and refrigeration systems and on the other hand as part of an energy multi-system.

What other advantages does your cold energy storage system offer?

The use of our cold accumulators allows you to optimise the management of energy consumption (cooling and heating systems). Thanks to the synergy effects with photovoltaic and wind turbines, ICE-ON increases the efficiency of renewable energy sources. Thus, the use of ICE-ON contributes to “peak shaving” and the reduction of greenhouse gas emissions.

What exactly do your customers pay for?

We offer our customers and partners a comprehensive package of services, from feasibility studies and design assistance to monitoring the execution of installation and maintenance. As the manufacturer of the ICE-ON cold storage tanks, we also offer the delivery of the products and the training of the craftsmen. In addition, there is the possibility of obtaining the software solution for the remote control program. This can generate further income on our side.

Since you are manufacturing a cold energy storage system, energy companies are certainly among your customers, right?

That’s right. In general, we are open to a wide range of opportunities for cooperation with companies from the renewable energy sector and with their system providers. But we are also interested in cooperating with industry associations, governmental organizations and research institutes. We operate both nationally and internationally.

Is your product, the ICE-ON cold accumulator, already usable? And what else do you want to achieve this year?

The first pilot projects confirmed the advantages of ICE-ON batteries. We have already initiated a research project at the Fraunhofer Institute. Here tests are being carried out with regard to the technical data. In addition, we analyze the effects of ICE-ON batteries on the German energy industry. Production will then start at the end of this year. We currently prepare and implement the first pilot projects on the German market.

Dariusz, thank you very much for the interesting interview! We wish ICE-ON Batteries only the best during this time and are curious how you will develop further. If anyone wants to know more about the project, they can check out your Innoloft profile and your requests.

Instagrid is the startup of the week 45: Portable Power for Professionals

Energy Storage, Uncategorized

A portable power supply can be used in many places: At events, on construction sites or when redesigning the garden. As there is no sustainable solution for this yet, e.g. diesel generators are used at construction sites. The disadvantages are certainly clear for everyone. Our startup of the week, instagrid, closes this technological gap with its innovative battery storage systems. In our interview with founder Sebastian Berning we learn more about it.

Hey Sebastian! I’m glad you’re here today. We start directly with a short question. In one sentence: What does instagrid develop?

instagrid develops and markets the most powerful mobile battery storage systems for professional users currently available on the market.

That sounds very interesting. Can you explain to us in more detail which technology you developed?

instagrid has developed batteries that can be recharged without the need for additional converters or converters on the usual mains supply and can also provide this voltage again at high power. You can imagine this as if you don’t need a charger to charge your smartphone, or if you could use your car battery to power a drill directly. Since the characteristics of these new batteries are largely defined by the complex software of the batteries, we call the technology a software-defined battery. The technology is aimed exclusively at converting electricity and can be combined with any battery cell, e.g. lithium-ion batteries or lead-acid batteries.

At the beginning of the interview you described your batteries as “light” and “compact”. Are those in addition to its “mobility” also your USP?

Since our batteries do not require power converters, they can be used to create systems for grid applications that are more compact, lighter, more cost-effective and more powerful than conventional systems. We currently use the technology to develop portable energy storage devices for professional users. Our customers come from the construction industry, horticulture or event technology, for example, and save a lot of time that they previously spent laying power cables and searching for sockets. In addition, you can be sure that you always have a suitable power connection on site, without having to carry a power generator with you. Our battery power supplies are about 50% lighter and 65% smaller than other equipment on the market and are the only systems that provide full mains power to operate large equipment such as high pressure cleaners. Nevertheless, the units are absolutely waterproof, as no ventilation is required for cooling.

And how do you distribute your product?

On the one hand, we develop white label products based on our battery modules for large customers. These products are developed, certified and manufactured in cooperation with our suppliers. The products are then distributed by the white label customers themselves and we provide after-sales services on request. On the other hand, from 2020 we will offer our battery storage systems under our own brand for mobile power supply. These batteries will then be offered exclusively for rental online via a direct-to-customer service model. In this way, we hope to be able to offer very low & fair entry prices, as a usage-based component is charged in addition to a monthly basic fee.

You have already mentioned your customers who come from many different industries. Do you also adress different markets?

We are currently addressing the market for mobile power generators, which comprises several billion euros worldwide. We believe that this market can grow rapidly if a reliable and comfortable electric solution is available – as has been seen with pedelecs / e-bikes in recent years. In addition, we are already addressing other markets with pilot customers, such as compact solar storage units for rental apartments in the city or electrical reserve canisters for electric cars. We are currently testing the latter with Norwegian and Finnish automobile clubs. Since Scandinavia often plays a pioneering role when it comes to sustainability, we have had an office there since last year that coordinates our business development activities. Our products are sold internationally, outside the EU, for example in the USA.

This brings us to the last question: Where do you currently stand with the development of your technology? I’m sure you’ve been working hard at it since your founding.

We are currently industrializing our first series products with several brand partners. The technology is largely mature and is currently being put through its paces by these partners under laboratory conditions and in the field. 2019 was already a very successful year for us. After our seed financing in January, we were able to build up a great team and were awarded a prize money of €100,000 by InnoEnergy in spring as the world’s most innovative energy storage start-up.

Sebastian, thank you very much for the exciting interview! We wish you continued success and hope to hear more from you. Those who are interested in further information about you and your products can have a look at your Innoloft profile.

m-Bee is the startup of week 44: Next generation of battery storage systems

Energy Storage

Many experts agree that renewable energies such as solar energy or wind power will play a major role in the energy revolution. But the central question is: How can a stable power supply be guaranteed if there is no wind or if the sun is covered by clouds? Basically, the answer is simple. The power needs to be stored. However, practice poses numerous challenges, so that there are currently no efficient and reliable storage systems. Our startup of the week, m-Bee, wants to change this and therefore is developing innovative inverters for battery storage systems. A trend-setting technology about which co-founder Nam Truong tells us more in our interview.

Hello, Nam! Thank you so much for taking the time today. We start directly with the first question: How would you present m-Bee in a nutshell?

We set a new standard for large-scale battery systems with our new, modular inverter technology to accelerate the deployment of batteries in the power system and the mobility sector.

Behind this are certainly complex technological subtleties. Could you explain them in more detail using youur battery systems?

Sure. Battery systems consist of batteries for storing the energy and inverters that convert the stored energy to usable electrical energy for the electricity grid. Systems today use high-voltage battery packs with a nominal voltage of around 800 volts that are then connected to a large central inverter.
We use a different approach, where the large and bulky central inverter is replaced by decentralized electronics that are mounted on smaller battery modules with less than 60 volts. Instead of chopping the battery voltage to achieve the required AC-voltage for the electricity grid, our technology orchestrates and stacks the battery modules dynamically to actively build the required output voltage.

You have just compared your development with the systems that are currently used. In this context, could you give us some more details about the advantages of the m-Bee solution?

Our new inverter technology improves the design of battery storage systems. The achieved benefits are safe battery voltage, fail-safety, and an energy loss reduction of 70%. This directly translates to faster and cheaper deployment of battery systems and higher safety for your employees in production, installation, and maintenance.
The battery systems that use our technology are also more reliable with a lower downtime and offer higher efficiency, thus lower levelized cost of storage (LCOS).

And do you sell the battery systems as a whole or just your inverter technology?

We see ourselves as suppliers of inverters for battery system integrators. The business model is therefore a classic product model in a supplier setting, where we face a manageable, yet growing number of customers that serve as multipliers for our product.
We will offer an attractive price for our customers that is based on the market price, even though we offer significant benefits. Additional, more sophisticated functions, such as uninterruptible power supply or island grid capability will be unlocked for an additional fee, if required. We aim at providing tailored solutions for the needs of our customers.

Which market do you address with your business model and what potential do you see there?

We will first address the market for stationary battery storage systems in Germany. We are currently talking to the major battery system producers to test and improve our technology. As soon as we have the first products ready, we will not only ramp up our production but look to extend our market internationally. The global market for battery inverters in the stationary application alone is expected to grow to 3.4 billion Euros by 2025 and is expected to keep growing rapidly.
Because we have a versatile system that is software defined, we can quickly move to other applications, such as battery-buffered DC-charging stations for electric vehicles and the power train of electric vehicles, as well. This will be our goal in the medium term.

m-Bee was founded at the beginning of this year and has already achieved a lot since then. Where do you currently stand with the development of your product and which goals do you want to achieve in the near future?

We are currently testing our first prototype system with a rated power of 100 kW at a pilot customer’s site. We will consider the learnings on the development of the next version that will serve as basis for the required certification and optimization for the production. The scheduled market launch of our first product will be by the mid of 2020.
We are currently looking for our first investment round with a 7-digit investment size. We invite investors to become part of m-Bee and set the next standard for battery systems.

Nam, thank you very much for the exciting interview! We wish you much success for the product launch and hope to hear a lot more from you! Those who are interested in supporting your corporate development are welcome to take a look at your Innoloft profile.

Take off together with METRO as pilot customer

Energy Efficiency and Environment, Energy Storage, IT & ICT, Smart City & Buildings

Together with METRO we started a new Challenge. Now we are looking for startups with innovative ideas who wants to bring them to market together with METRO. You can apply for it until July 23rd 2019 with your cooperation idea at METRO, a leading international specialist for wholesale and food retailing.

You can win METRO as a pilot customer for your paid innovation projects. METRO turnover was 37 billioon Euro in 2017 / 18. More then 150.000 employees work for METRO worldwide.

We are looking for digital solutions for the METRO Stores in the following areas decentralised power generation and storage, IoT networked buildings, energy-efficient buildings as well as innovation ideas for METRO customers in the restaurant sector.

As part of its digitization strategy, METRO wants to invest in new innovative solutions – products, business models, process improvements.


ENERGIELOFT supports METRO in the selection of suitable ideas. You submit these to us. If your cooperation ideas are short-listed, you can spend half a day with a METRO employee at the company headquarters in Düsseldorf. There you will discuss your idea personally. Afterwards you will present it to a panel of experts. Once you’ve convinced them of your cooperation idea, you’ll start the paid pilot project together with METRO. If the implementation is successful, you can look forward to a long-term cooperation with METRO.


All startups not older than ten years can apply worldwide.

Further information on the Challenge and the application you can find here: METRO Startup Challenge