Frequently Asked Questions


Who is SkyCool Systems?

We are a team of innovators and scientists focused on reducing the energy intensity of buildings with our passive cooling panels. Our cooling panels reject heat to the sky 24/7, and can cool to sub-ambient temperatures even during the day. We are dedicated to using our technology to bring efficient, climate-friendly cooling to all parts of the world.

Where is SkyCool Systems based?

We are based in Mountain View, California.

What problem is SkyCool focused on solving?

As global air temperatures rise, the demand for cooling is expected to grow. Air conditioning and refrigeration systems consume massive amounts of energy and are responsible for emitting significant amounts of greenhouse gases to our planet. The International Energy Agency (IEA) expects the energy demand for space cooling to triple by 2050. Without aggressive measures to increase the efficiency of air conditioning and refrigeration systems, we face overburdened electrical grids, increased GHG emissions and even warmer global temperatures. At scale, our passive cooling solutions offer significant energy, demand, and cost savings with a footprint that is smaller than a typical solar panel installation.

Why choose SkyCool Systems?

With a simple retrofit to a new or existing cooling system, SkyCool will provide a low-maintenance, cost-saving solution which operates silently, 24/7, with substantial electricity savings and zero water use. Our elegant and simple solution mitigates climate change, reduces urban heat island effects, and saves you money.

About Radiative Cooling

What is radiative sky cooling?

Radiative sky cooling occurs naturally because Earth’s atmosphere is partially transparent to infrared thermal radiation (the light wavelength associated with heat). Due to this effect, sky-facing surfaces emit more energy as thermal radiation to the sky than they receive from it. Radiative sky cooling occurs all the time, however is typically not observed during the day. Through the use of advanced materials engineering, we were the first to demonstrate materials which can stay cooler than the ambient air temperature, even under direct sunlight.

Who first discovered/used radiative sky cooling?

Radiative cooling is a natural phenomenon that humans have observed for centuries. Ancient Persians and Egyptians learned to use radiative cooling in the desert to make ice at night, which they used for food preservation. You probably have observed the radiative cooling effect if you have ever seen water condense or frost on the windshield of a car in the early morning.

What is innovative about SkyCool Systems’ approach to radiative cooling?

Prior to SkyCool’s work, the effect of radiative cooling was not observed during the day. This is because outdoor, sky-facing surfaces heat-up when exposed to the sun. Our research resulted in the creation of multilayered films that reflect nearly all incident sunlight and emit energy in the mid infrared frequency range between 8 and 13 micrometers. As a result, our panels will be cooler than the air temperature in the middle of the day, when directly exposed to the sun.

SkyCool Panel System

What do SkyCool panels do?

SkyCool Systems has developed a hydronic panel that can improve the efficiency of air conditioning and refrigeration systems. Our panels cool a circulating fluid, typically water-glycol, and we use that fluid to remove heat from buildings and the condensers of cooling systems.

How do SkyCool panels work?

The cooling effect from SkyCool Systems’ panels is enabled by a multilayer radiative cooling optical film. The film reflects sunlight to prevent the panels from heating up during the day and also emits infrared heat to the cold sky, which cools the panels and the fluid running through the panels. The cooling effect of the panels occurs 24/7.

How can the sky be a renewable resource?

The sky is one of the coldest resources we have simply because it is in close proximity to outer space. Normally, we do not have access to transmit heat to the upper atmosphere, but with the use of radiative cooling, our panels can emit heat from buildings to the cold sky and space, 24/7/365.

Does SkyCool Systems’ array generate or use electricity?

Our panels do not require electricity to cool, nor do they generate electricity. Our system will require a pump to circulate the water. This is the only source of electricity consumption. The panels save electricity when connected to air conditioners and refrigeration systems, and in some circumstances can be used to replace air conditioning systems.

What are the operation and maintenance requirements?

Our panel system is designed to be simple and reliable. The panels have no electrical connections and the system does not require any interconnection to the grid. The only maintenance requirements are a light cleaning with water every six to eight weeks during lengthy dry periods.

Where have these panel systems been tested?
Currently SkyCool has completed commercial pilots in California. We are working with early customers to complete further deployments in the West, Midwest and Southern parts of the United States. Check out our case studies to learn more.
What types of AC or refrigeration can your panels connect with?

Our panels will connect with any vapor compression cooling system. In some cases, the panels can even be used to replace air conditioning systems.

Can I integrate SkyCool panels/film with solar panels?

This is not something that we’re currently developing and would require a redesign of a solar module.

How large are the panels? How much do they weigh?

The panels were designed to have the same form factor as a commercial solar module. Our panels are 21.5 square feet (2 square meters) and weigh 27 lbs (dry weight).

How are SkyCool panels installed?

The panels are connected together with push-to-connect fittings. A typical installation will involve the creation of a closed hydronic network of panels on the roof, where a small pump circulates water/glycol from the panels to a plate heat exchanger installed on the refrigerant piping of the condenser. The heat exchanger is installed by refrigeration contractors and the panels are set up on a roof with conventional solar racking and solar labor.

How effectively does your material reject heat when it is cloudy?

Clouds will reduce the efficacy of radiative cooling. Reduction of performance ultimately depends on how high and cold the cloud is (in general, high clouds are colder, low clouds are warmer). Low fog will be the hardest environment to operate in and can reduce cooling performance of the films and panels by approximately 30%.

Integration of our panels with refrigeration and air conditioning equipment will be much less influenced by cloud cover. Days with high cooling loads and warm air temperatures are often correlated with fewer clouds or high scattered clouds. Additionally, using our panels on refrigeration and air conditioning equipment, means we are cooling fluids that are initially above the ambient air temperature. When it is cloudy out, we are still able to provide cooling but more of the cooling will come from convection as opposed to radiation.

How are the panels disposed of at end-of-life? Are there any materials that would be classified as hazardous waste?

Our cooling panels do not contain any hazardous materials. The panels themselves are largely made of aluminum and can also be recycled at the end of life. The design of the panels longevity is commensurate to the lifespan of most mechanical HVAC equipment.


Are your solutions readily available for businesses?

Yes, we are currently working on deploying our technology in the commercial and industrial refrigeration market.

What applications are you focusing on for your early deployments?

For our panel technology, we are focused on applications in:

  • Data closets with cooling loads less than 10 tons
  • Data centers and distributed compute facilities
  • Refrigeration systems in supermarkets and industrial cold storage facilities.

For non-panel based applications, we are testing our passive cooling technology with outdoor electronics, shade structures, battery storage systems, metal roofs and transport.

What regions and geographies is SkyCool focused on for 2021?

We are focused on completing pilot deployments and projects in the United States. Additionally, we are currently only focused on applications in the industrial and commercial sectors where cooling is a dominant load.

How can businesses utilize your solutions to save energy and reduce emissions?

The cooling effect from our panels occurs all day and is very well aligned with the 24/7 operation of refrigeration and air conditioning systems in supermarkets, refrigerated warehouses, data centers, hospitals, convenience stores, office buildings, and restaurants with walk in freezers. There are also numerous uses and direct applications of radiative film to reduce heat load including rooftops, outdoor shaded structures, refrigerated trucks, auto, rail and other transport, etc.

Are your panel and film solutions readily available in the residential space?

We are not currently providing applications of our technology in the residential space. If you are interested in using SkyCool’s panels on your house, sign up here for future updates.

Partners & Installers

I’m interested in completing a pilot deployment. What is the best way to proceed?

We are looking for deployments with persistent cooling loads like those found in commercial and industrial refrigeration systems, as well as data closets and data centers. Please contact us to learn more if you think your site might be a good fit.


Is SkyCool working with contractors for installation and service?

We are looking for local HVAC/R, solar thermal and solar PV contractors and installers for projects in the United States. Contact us if you would like to learn more about installing our system.



Is SkyCool Systems looking for investors?

We can only accept investments from accredited investors and investment firms. If you are an accredited investor and are interested in speaking with us, please contact us.