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SunOyster cooling

Periodic Reporting for period 1 - SOcool (SunOyster cooling)

Reporting period: 2016-08-01 to 2017-01-31

Cooling is needed for air-conditioning of rooms where annually more than 100 million of small air conditioners are sold annually (world market volume 73 Billion USD) and for refrigeration mainly of food (90 bn USD). Together, the direct emissions of refrigerants and the indirect emissions of the electricity generation for cooling cause totally 7 % of the global greenhouse gas (GHG) emissions (see

For society, this means
- climate change (rising temperatures, changed rainfall, more extreme weather and rising sea water levels), leading to more cooling demand, water scarcity, hunger, storm damages, flooded land and cities, mass migration),
- depletion of fossil fuel reserves, in particular oil and gas,
- local pollution through e.g. fine dust emissions of coal plants generating the electricity for cooling and
- high costs of energy generation, in particular through the import of fossil fuels.

The overall objective of the project "SunOyster cooling - SOcool" (see attached in Picture 1 the SOcool logo) is to establish different possibilities of cooling with the help of the SunOyster and electric and thermal chillers. The SunOyster is a concentrating solar technology using parabolic mirrors to concentrate solar radiation on a line (see attached a photo of the SunOyster). In that line, the hybrid receiver (using a secondary concentration and concentrator cells) converts the direct radiation with 30% efficiency into electricity and with 45% efficiency into heat of up to 170°C. The electricity can drive electric chillers, the heat different kinds of thermal chillers.

As the refrigerants of thermal chillers have no GHG potential, they automatically reduce the direct GHG emissions from cooling activities. The SunOyster uses the renewable solar energy to generate the cooling. Thereby, the emissions of GHG from cooling activities can be strongly reduced. Fossil fuels are preserved, local pollution is reduced and the cost of energy supply is minimised.
1. Together with the external consultant validation and aggregation of different reference cases for the SOcool packages, based e.g. on SHC Task 48.
2. Literature study on previous solar cooling projects.
3. We asked Solargis to prepare an innovative map comparing direct normal irradiance (DNI) and global horizontal irradiance (GHI).
4. Design of the five SOcool packages P1 to P5 (Product Plan), providing highly energy and cost efficient and scalable solutions for each package.
5. Discussion with chiller manufacturers and others about economic sweet spot and cost curve over scale.
6. Price benchmarking of our resulting packages P1 to P5 against the reference cases.
7. Selection of typical markets for the feasibility study (Case Study).
8. Based on standardized questionnaire, collection of detailed framework conditions for Marketing Study (energy prices, renewables incentives) in the selected markets, using agencies and selected agents as well as own travel (to Dubai, India, China).
9. Strengthen links with existing partners such as chiller manufacturers, identify additional collaborative partners in the markets, discuss strategic demonstration plants and pilot studies and opportunities.
10. Development of a detailed demonstration strategy to be formulated based on discussion with potential collaborative partners, including developing pilot trial methodology (according to SHC 48), with the aim of maximizing market awareness and acceptance; conducting target customers groups interviews/ surveys.
11. Strategic decisions on attractive packages and markets (Road Map).
12. Forming collaborations with the most suitable suppliers.
13. Preparing a feasibility study report in long version (65 pages with approx. 50 pages attachments). Based on that we prepared the short 20 page report.

Main results are:

The literature study shows attractive applications and configurations of solar cooling, but also that the SunOyster has to achieve significant cost reductions in solar cooling (which it can, as shown below).

Both electric and thermal chillers have advantages. For the SunOyster, thermal chillers are more attractive because they allow a good use of the heat in permanently warm climates or during the summer season. Among the thermal chillers, small Lithium Bromide (LiBr) absorption chillers with in-built fan are the best option for smaller scale air conditioning, ammonia chillers for refrigeration and more efficient double stage LiBr chillers for larger air-conditioning.

The project developed a marketing plan for considering markets are attractive for SunOyster cooling. This is defined by the following five criteria:

- An innovative map prepared during the project shows where the direct normal Irradiation (DNI) needed by the SunOyster is better than the global horizontal Irradiation (DNI) which is relevant for conventional solar PV and thermal equipment (see attached Image 3). Whereas the equator regions are not favourable, there are broad sun belts north and south of the equator which are favourable for the SunOyster.
- Cooling demand can be expressed in cooling degree days. Many areas in the sun belts have a high cooling demand.
- Countries with large cooling markets such as China, US and India are more attractive.
- Markets with higher energy prices such as e.g. Italy are more attractive.
- Positive framework conditions for solar energy support SunOyster cooling.
-We have summarized these factors in the attached Image 4. First target markets of the SunOyster are Italy and India.

In the case study, we identified for the markets Italy (Catania) and India (Mumbai) attractive applications. For the small scale applications in Italy we attach Image 5 and for the large scale applications Image 6. Because of higher radiation and energy costs, Italy is even more attractive than India. Attractive applications for the SunOyster are in particular family houses with swimming pools, offices, cold storages and Hotels (see in detail the text field below).
The SunOyster is over the state of the art of PV and solar thermal a progress because thanks to its solar co-generation it
- reduces the cost of electric power by one third compared to PV and the cost of thermal power by two thirds compared to vacuum tubes;
- reduces the cost of electric energy and of heat accordingly;
- achieves higher temperatures (170°C) than non-concentrating solar thermal Systems and
- gets most energy out of a given horizontal surface, in particular in the version SunOyster pvplus.

Based on the high competiveness of the SunOyster for solar thermal cooling, the project compared to the state of art four innovative product packages. Looking at the example of Italy:

Package P2 SOcool Pool consists of at least one SunOyster and a very small LiBr multi-split chiller with indoor units for a family house with pool. The waste heat of the chiller and the winter heat of the SunOyster is injected into a swimming pool. Compared to the reference case (electric chiller powered by the grid and oil boiler) it saves not only large amounts of primary energy, but can also achieve an internal rate of return of 36.8%,with cost reduction from mass-rollout even 68.5% and payback time on equity of 1 year.

Package P3 SOcool Office consists of several SunOysters with a LiBr absorption chiller for an office. The sunshine hours and the office hours match well. IRR 36.8 (53.7) %.

Package P4 SOcool Cold Storage is a modular cold storage optimized for SunOyster Installation where the SunOyster heat and the thermal chiller cover the base load of cooling and the SunOyster electricity with an electric chiller the peak load and the very low temperatures.

Package P5 SOcool Hotel consists of many SunOysters with a highly efficient double stage LiBr absorption chiller. The waste heat from the chiller is pre-heating sanitary warm water or heating pool water (tri-Generation of electricity, cold and heat). IRR 38.7 (47.2) %.

Altogether, the realization of the SOcool project in the next Phase will not only have the positive Impacts on society outlined in the first text field. It will also lead to a fast growth of turnover, profits and number of employees of SunOyster Systems.
Image 3 world map comparing DNI to GHI
Image 4 graph attractiveness of SunOyster cooling
Image 5 table small SunOyster applications
Image 1 SOcool logo
Image 2 photo of SunOyster with clouds
Image 6 table large SunOyster applications