earth Water is a research and development project focused on direct solar desalination. The project explores low-tech methods to convert ocean saltwater into freshwater using concentrated solar energy. It is primarily intended for smallholder farmers in regions affected by water scarcity.

The project is based on the observation that water scarcity is not caused by a lack of water overall, but by a lack of accessible freshwater. Large quantities of water are present in oceans, while freshwater resources are unevenly distributed and increasingly strained.

Freshwater groundwater resources, particularly in coastal regions, are being depleted due to increased usage and rising temperatures. Climate change intensifies this process by altering precipitation patterns and increasing evaporation. In addition, saltwater intrusion occurs when seawater penetrates freshwater aquifers, further reducing the availability of usable groundwater.

earth Water investigates direct solar desalination as an alternative to conventional desalination methods. Today, most desalination systems rely on reverse osmosis, which requires significant energy input and is often powered by fossil fuels. These systems are complex, expensive to maintain, and difficult to deploy at small scales.

The approach used in earth Water relies on direct solar thermal desalination. A parabolic dish concentrates sunlight onto a focal point, generating high temperatures. Saltwater is heated, evaporated, and then condensed to produce freshwater. The process consists of four basic steps: concentrating light, heating water, condensing vapor, and collecting freshwater.

The system is designed to be simple and replicable. An important requirement is that it can be built using widely available and affordable materials. The goal is to enable local production and maintenance without reliance on advanced infrastructure, rare materials, or specialized components. Sustainability is considered throughout the design process.

Direct solar desalination has historically seen limited commercialization due to lower efficiency compared to reverse osmosis systems powered by solar panels. However, it offers advantages in simplicity, reduced material complexity, and independence from rare earth elements. The system relies directly on thermal energy from the sun rather than electricity.

The project considers applications within food systems, particularly small-scale agriculture. Desalinated water can be combined with efficient irrigation methods such as drip irrigation. This can help address limitations in arable land and reduce pressure on freshwater sources.

Beyond water production, earth Water is intended to support local innovation. The development and assembly of systems could create local employment opportunities and encourage technical knowledge transfer. By focusing on decentralized systems, the project aims to reduce dependence on centralized water infrastructure.

From an innovation systems perspective, entrepreneurial activity in water-saving technologies is present, with several startups and investments emerging, though scalability remains uncertain. Knowledge development in solar technology and desalinated water for irrigation has increased rapidly. Knowledge diffusion through networks exists but remains limited, indicating a need for broader sharing and collaboration.

Policy frameworks such as the EU Water Framework Directive emphasize the protection of water resources, and markets for water-saving technologies are expected to grow, particularly in agriculture and controlled environments. While niche markets for direct solar thermal desalination currently exist, long-term climate and emissions targets increase interest in low-energy solutions.

earth Water addresses the need to reduce reliance on groundwater resources and to explore alternative water sources. The project focuses on feasibility, simplicity, and adaptability rather than maximum efficiency, aiming to contribute to resilient water systems in water-scarce regions.