The national priority axis is increase of renewables (RES) use in Latvian Energy sector; therefore, new solutions for Electricity, Heat and Cold production are sought for. Solar energy is available at the same time when there is need to cool rooms, so Solar Cooling systems are suitable also for Latvian conditions. In Latvia such systems are not used yet, so it is important to assess the potential of these systems. The sunlight duration and intensity depends on the season, weather conditions and geographical position of a country. As compared with the annual global solar radiation incident on horizontal surfaces in sunny regions (2200 kWh/m 2 ), in the northern Europe is half as much (1100 kWh/m 2 ). The solar energy potential defined for Latvia as technically achievable by 2020 is: for electricity 0.01 TWh and for heat 0.04 TWh. As shown by experimental studies, the application of solar collectors in Latvia can give good results. The energy of solar radiation can be employed for 1700-1900 hours annually. Due to a gradual increase in the comfort level, the demand for space cooling will grow in the near future. Solar cooling can be an alternative for electrically-powered compression-type chillers that currently are the most common in the Baltic States. The solar cooling system installed in the Institute of Physical Energetic is the first of the type in EU which is built at the latitudes higher than 55 degrees of north. Taking into account the fact that there were no systems plants of this type at so "cold" latitudes, first of all the models in PolySun were to be validated, and a dynamic simulation program containing the five-years meteorological data was to be developed. The solar cooling system has been optimized using multiple simulations. The influence of the system's different elements on its operation is evaluated. The optimal model developed for the given climatic conditions is described.

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Abstract. The main directions of efficient, balanced market-based energy policy of Latvia are set out in the informative report "Long-Term Energy Strategy 2030 -Competitive Energy for the Society", one of the main objectives of the strategy being to ensure a positive impact of the energy sector on the Latvian economysustainable energy, it means to reduce dependence on energy imports, to promote new, efficient technologies for the use of renewable energy and carrying out of energy efficiency improvement measures. It is fully in compliance with the operational strategy of the Ministry of Agriculture of the Republic of Latvia for 2017-2019 and related to the EU's progress towards the development of the bioeconomy as a crucial element in the challenges of today's global change. Resource depletion and increasing impact on the environment greatly increase the demand for food as well as competition for resources, including agricultural land. Regarding the development of sustainable agricultural development, it is necessary to prepare a platform for the development of bioeconomy, taking into account related policies and their objectives, integrating bioeconomic principles in order to ensure the production of high added value products, to promote scientific and business synergies and innovations in production, create well-paid jobs in rural areas, reducing dependence on fossil resources, sustainable use of renewable resources, by preserving of biodiversity and climate change mitigation. Rational energy efficiency increasing in agriculture is the main way to self-sufficiency. Nowadays, there is high potential of renewable energy source applications in different processes of the agriculture sector. Energy demand extrema in milk production is close to solar radiation extrema. This opens wide opportunities of solar technology application. Deep analysis shows that there exists a gap in solar radiation peak and electricity demand peak. It means that energy accumulation is needed for higher performance. The publication describes comparison of different solar energy accumulation type application in the milk production sector. Comparisons include pros and cons of electrical and thermal solar energy accumulation. Keywords: solar energy, photovoltaic (PV), electricity accumulation. IntroductionRenewable energy and farming are a winning combination. Wind, solar, and biomass energy can be harvested forever, providing farmers with a long-term source of income. Renewable energy can be used on the farm to replace other fuels or sold as a "cash crop" [1].The amount of energy from the sun that reaches the Earth each day is enormous. All the energy stored in the Earth's reserves of coal, oil, and natural gas is equal to the energy from only 20 days of sunshine.Photovoltaics (solar electric panels) can power farm operations and remote water pumps, lights, and electric fences. Buildings and barns can be renovated to capture natural daylight, instead of using electric lights. Solar power is often less expensive than extending power lines.The ...

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