Digitization Helps Nemo’s Garden Create Alternative Agricultural Opportunity

Underwater activities just got smarter

Published: Tuesday, July 19, 2022 - 11:03

One question led the founders of Nemo’s Garden, a subsea farming platform, to embark on its mission to take agriculture beneath the waves and bring better harvests to market: “Seventy percent of the planet is covered by water. Why don't we try to use part of the ocean to make more food, in a better way?”

The team has already successfully grown a variety of plants in this alien environment, and with help from Siemens, they’re looking to digitize the process so they can scale the project, validate the benefits their crops bring to the table, and expand their operations.

Project overview

The goal of Nemo’s Garden is to create an alternative agriculture system for areas where environmental, economic, or morphological reasons prevent traditional plant growth. The company has developed a prototype biosphere in which plants can be grown underwater. The biosphere can leverage the readily available, positive environmental factors in oceans or other bodies of water, such as temperature stability, water evaporation, CO² absorption, abundance of oxygen, and natural protection from pests.

Although they have been able to prove the concept of their underwater biospheres through a series of innovation cycles, the current structure is expensive to produce, transport, and deploy. Heavily manual monitoring of the processes during the growth cycle further increase these costs. So, Nemo’s Garden partnered with Siemens for software, hardware, and services to enable the team to refine the biosphere’s design and automate processes to turn this concept into a commercially viable subsea farming platform that can be deployed globally.

Inside the marine biosphere

Nemo’s Garden is a series of biospheres submerged in water, which provides the growing environment, insulates the plants from direct sunlight, and creates desalinated water through evaporation. The atmosphere within the biospheres must be carefully controlled to prevent high humidity or temperatures that would harm the plants. By using Siemens’ NX product design and engineering software to model the domes digitally, the team can optimize the position of sensors, air circulation fans, and much more, based on the growth patterns of the plants inside.

Digitization enables faster innovation cycles

Harsh winters and short summers limit Nemo’s Garden to one growth cycle a year, which in the past has meant only one innovation cycle per year because changes to the design of the biosphere or materials couldn’t be tested in the real world until the next growing season. However, by leveraging Siemens’ Xcelerator portfolio, Nemo’s Garden was able to create a comprehensive digital twin of the biosphere, the growing conditions, and the impact of the biosphere on the ocean or body of water in which it’s located. A digital twin is a virtual representation of a physical product or process. It’s used to understand and predict the physical counterpart’s performance characteristics. With a digital twin, innovation continues in the virtual world because changes and improvements can be tested through simulation to refine the designs and processes at a massively accelerated rate, including system simulation, manufacturing, operations, and life-cycle analytics.

Diver photo taken with Olympus digital camera

Bringing an idea to life—such as growing plants underwater—is a feat of will for a company. Determining how the product or service can be scaled to success is the greater challenge for many businesses. Making that great idea successful is the major impetus behind  digitized solutions.

Digitization augments the flexibility of small companies and startups by leveling the playing field between the Davids and the Goliaths of industry. Digitization can be a valuable tool in lessening the need for large development teams because it can fill in knowledge and even systemic gaps that inevitably exist. For example, it may be premature for a startup to have a dedicated simulation engineer on staff; however, a comprehensive digitized solution can equip an existing team member with the right software tools to span the gap until the business grows. Digitization can provide startups with the specific workflows and environment their business needs to enable their employees to innovate.

The digitization journey

A wealth of historical sensor data collected by the Nemo’s Garden team over previous seasons was used to develop the initial digital twin of the biosphere. Then, during the 2021 growing season, live data collected from cameras and sensors in the Noli installation were fed into the models to compare the predictions to what was happening in real time. Simulation was used to tweak the models until they perfectly matched their physical counterparts.

“70% of the planet is covered by water. Why don't we try to use part of the ocean to make more food, in a better way?”

Siemens is now using the validated simulations of today’s biospheres to generate optimized designs for a next-generation bio-tunnel that is less expensive to produce and easier to transport, deploy, and monitor remotely. This will move Nemo’s Garden ever closer to achieving its goal of commercial viability.

Shaped more like a bullet train than a dome, the new design has the thinnest possible shell, polymer ties rather than metallic chains, as well as an optimized orientation to the coastline, and an internal shape that maximizes air circulation and condensate collection. The elongated form is closer to onshore vertical farms, which makes it possible to apply a similar approach to automating the processes, including monitoring and harvest.

Subsequent steps will include automation strategies for retrieving the harvest; mechanisms for changing the location, orientation, and depth of the platform in response to meteorological conditions; and creating sustainable closed-loop aquaculture systems that cluster Nemo’s Garden’s biospheres with shrimp and fish farms. Additionally, this next-generation bio-tunnel is designed to fit neatly into a shipping container for easy transport. This is where Siemen’s Xcelerator Portfolio comes in.

Siemens Xcelerator portfolio

Nemo’s Garden has access to the full breadth of Siemens Xcelerator—an integrated portfolio of software, services, and application-development platform that can be personalized and adapted to fit customer and industry-specific needs to help companies of all sizes become digital enterprises.

Xcelerator combines the full portfolio of Siemens’ software for design, engineering, and manufacturing with an expanded Mendix low-code, multi-experience application-development platform. The Mendix platform now includes cloud and app services for digital engineering and the internet of things (IoT) powered by MindSphere, the cloud-based, open IoT operating system from Siemens, in addition to Mendix’s unified low-code and no-code development environments. Unique to Xcelerator, this platform drives digital transformation by enabling anyone in the ecosystem, including citizen developers and engineers, to easily build, integrate, and extend their existing data and systems.

The company also announced that Siemens PLM Software has become Siemens Digital Industries Software, a change intended to reflect the growth in the company’s ecosystem and portfolio of solutions, applications, tools, and services that drive digital transformation at organizations across the globe.

Examples of technology used by Nemo’s Garden

A digital twin of the existing biosphere was subjected to pressure and distortion tests using Finite Element Method modeling to identify ways to optimize the design. By placing the digital twin of the biosphere in a simulation of the Bay of Noli, the team was able to identify the flow characteristics of the water around the sphere and identify the highest points of flow for future power-generation microturbines.

The same model and tidal history was used to calculate stresses on the chains holding the sphere to the seabed as well as the protective effect of the sphere cluster on beach erosion. Additionally, the same computational fluid dynamics capabilities were applied inside the sphere to predict how thermal currents created by sunlight would move around the growing plants, and under which daylight conditions fans would be required.

Monitoring and automation

The live video that Nemo’s Garden streams on YouTube is also being uploaded into the MindSphere IoT platform. By comparing this footage to video stills of the target crops at various stages of growth and in various conditions of health in traditional on-land farming operations, Siemens Technology in Princeton, New Jersey, is training a machine-learning algorithm to monitor all aspects of the underwater growth and predict the optimum harvest times for each crop. This algorithm, deployed onto a SIMATIC Edge microcontroller placed in the biosphere, tracks the plants’ status and feeds the information into a Mendix dashboard, which enables the Nemo’s Garden team to remotely monitor the plants throughout the season from anywhere in real time. Previously, information could only be collected manually by divers.

Data analysis from Nemo's Garden

Additionally, the machine-learning algorithm will be connected to actuators for air circulation, humidity control, irrigation, and nutritional dosing—creating an agricultural service that is optimized for subsea operations. This will be tested this winter in a specially deployed deep-sea biosphere, farther offshore in Noli, as well as in a dry shadow system set up in the MxD digital manufacturing center in Chicago, where Siemens plans to engage potential industrial partners to explore avenues to scale up operations.

The subsea biosphere environment

When evaluating the design and construction of biospheres, it’s also critical to understand and minimize the effect of the structures on the surrounding environment. The biospheres provide an artificial reef environment by slowing the current around them, but the team at Nemo’s Garden wants to evaluate and mitigate any negative effects the structure might have in the long term. How do anchor points affect sea-floor life? How are the currents around the biospheres affected?

Simulation helps answer these questions early on so they can be addressed before costs become unmanageable. Additionally, combining existing biosphere data with weather predictions can also improve plant growth within the biosphere. Sunny days produce more heat and humidity inside the biospheres, so the system will have to accommodate the variation.

Siemens technologies process and methods

An important thread throughout the process, from construction to deployment, is the need to carefully monitor the environment both inside and outside the biospheres to ensure optimal growing conditions. This is traditionally a heavily manual process performed by trained divers from within the biospheres. However, digitization—specifically, using artificial intelligence and machine learning—makes it possible to do this remotely from anywhere.

Nemo’s Garden diver 

With each biosphere outfitted with a sensor and controls suite, environmental and growth data can be captured and analyzed. Some of these data directly controls operations within the biosphere; fan speed, for instance, will likely be controlled locally. The data are also sent ashore to create AI and ML models of the growth patterns within the biospheres. One such model leveraged visual data from terrestrial growth and previous growth seasons within the Nemo’s Garden biospheres. The model is used to understand the timeline for harvesting the plants at their peak for nutrient content. 

For more information, see Siemen’s original articles, blogs, as well as the Nemo’s Garden home page. 

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