Sun-to-Liquid Technology

What are solar fuels?

Fuels made of air and sunlight.

Solar fuels are synthetic fuels produced from solar energy. They are climate-friendly, renewable, and affordable. A cutting-edge technology that offers a truly sustainable alternative to fossil fuels.

Why solar fuels?

Scalable.

Solar fuels are scalable to cover global fuel demand. They rely on abundant resources and non-arable land. Conflicts of interest with the food and other industries are avoided.

Affordable.

Solar fuels truly offer competitive prices with fossil fuels. Our technology is affordable thanks to a much higher energy conversion efficiency than other synthetic fuel technologies.

Compatible

Solar fuels are chemically akin to fossil fuels. There is no need to adapt the global fuel infrastructure. Our solar fuels are compatible with existing oil pipelines, refineries, and combustion engines.

Carbon-neutral

Solar fuels only release as much CO2 into the atmosphere as was used for their production. Therefore, net CO2 emissions are significantly lower. They can even be reduced to zero when CO2 from ambient air is used.

Independent

Ideal conditions to produce solar fuels can be found on any continent. The independence from fossil resources results in greater autonomy. Shorter transportation routes are another key asset.

Storable

Liquid fuels have a very high energy density and can be stored for a long time without compromising their quality. A winning combination of two non-negotiables for many fuel-consuming industries.

Versatile.

Kerosene, gasoline, diesel, methanol, hydrogen, synthetic crude oil – Synhelion technology yields any type of fuel. Solar fuels can rapidly adapt to changing demands and they can replace fossil fuels in all areas of application.

Eco-friendly

The entire life cycle of solar fuels is based on environmentally-friendly principles. The fuels are produced with renewable energy and emit not only less CO2 but also less noxious gases when they burn.

Synhelion uses solar heat to convert CO2 into synthetic fuels – so-called solar fuels. Solar radiation is reflected by the mirror field, concentrated onto the receiver, and converted into high-temperature process heat. The generated heat is fed to the thermochemical reactor that turns CO2 and H2O into syngas, a mixture of H2 and CO. The syngas is then processed by standard gas-to-liquids technology into fuels, such as gasoline, diesel, or jet fuel. Excess heat is saved in the thermal energy storage (TES) to enable continuous 24/7 operation.

Our solar fuels are compatible with the current infrastructure and reduce net carbon emissions by up to 100 percent.

Three Innovation Fronts.

Our solutions combine state-of-the-art solar tower systems with proprietary high-temperature thermochemical processes. The Synhelion technology is located at the top of the solar tower and unites three key innovations:

The solar receiver delivers clean solar process heat at unprecedented temperatures beyond 1’500°C.

The thermochemical reactor utilizes the solar heat to produce syngas.

The thermal energy storage (TES) enables continuous 24/7 operation.

Solar Receiver.

Our solar receiver is inspired by nature. We use the greenhouse gas effect to reach ultra-high temperatures. The cavity is filled with a greenhouse gas flowing from the aperture toward the back of the cavity. Typical gases employed are water vapor or mixtures of water and CO2. Solar radiation enters the cavity through a window and passes with minimal absorption through the gas. The black surface of the cavity absorbs the heat, thermalizes, and reradiates it back into the cavity. The greenhouse gas absorbs the thermal radiation and is heated up, acting as heat transfer fluid (HTF). Temperatures in excess of 1’500°C can be reached with unprecedented efficiency.

Our solar receiver technology is applicable to various industries using high-temperature process heat. 

Reactor

We develop two thermochemical processes and associated reactors to produce syngas. Additionally, we also develop reactors for the production of pure hydrogen.

How it works:

The reactor consists of multiple tube bundles. Each reactor tube is filled with a reactive material that enables the production of syngas. The heat transfer fluid flows through the reactor and provides the thermal energy for the chemical reactions inside the reactor tubes.

In the case of Solar Upgrading, a mixture of methane, water, and CO2 is converted into syngas at 800 to 1’300°C.

To produce carbon-neutral fuels, a mixture of water and CO2 is converted via a two-step thermochemical cycle into syngas at temperatures up to 1’500°C.

Thermal Energy Storage

Our thermal energy storage (TES) stores excess heat collected by the solar receiver during sunny hours. The hot heat transfer fluid (HTF) from the receiver streams through the TES from the top to the bottom and transfers its thermal energy to the solid storage material.

During the night or cloudy periods, the HTF flows through the TES in the opposite direction to recover the previously stored thermal energy. The hot HTF from the storage drives the thermochemical processes in the reactor, ensuring continuous operation – even in the absence of solar radiation.