Primary energy resource consumption in the world is surveyed in the work and oil yield, production and consumption evaluated on the world level, also showing its density in the view of several states. Oil reserves are evaluated and the states with biggest oil reserves stated. The research proves consumption of primary energy oil in the world is increasing continuously. There are primary energy resources to be acquired in Latvia evaluated and primary energy resources in means of final consumption divided between types of energy estimated.

The article presents the part of PhD studies of the energy wood harvesting technologies in thinning, and its development possibilities. A possibility for energy wood procurement and use in Latvia as a good amount of not used energy, including estimation of how much wood for energy purposes could be available in Latvia is analyzed. Research has been made in two parts using forest stands cutting area in three different ages to get an average volume of energy wood per ha. First part of the research has been done in a 60 years old forest stand cutting area in the way that total chips volume is measured and then recalculated to the thinning area. The average volume from studied forest stand was 20.32 m**3 haE-1. The second part of the study shows that from 30 till 45 years old forest stands cutting area by the measuring possible removal tress, the energy wood volume could be 23.74 – 33.5 m**3 haE-1. Including the slash from this forest stands cutting area the possible volume of wood for energy purposes could be ~ 33 – 47 m**3 haE-1. The calculations also have been done to study available energy wood resources from whole forest stands thinning area. Totally the available energy wood volume in Latvian conditions is 0.85 million m3 yrE-1.

The study was accomplished in 2010. The applied research methods are based on the analysis of the studies by other authors, industry experts, statistic data and the (unpublished) information provided by the Latvian district heating merchant “xxx”. Spearman’s rank correlation coefficient was used for evaluating data regularity. In 2020 the energy produced from renewable sources (Directive 2009/28/EC) in total energy consumption in Latvia has to reach 40%. Such an objective can be achieved by promoting the use of biomass at cogeneration (CHP) plants, the potential of which is the district heat supply system. Wood as an energy resource in its structure accounts for only 25-30%; therefore, the primary condition is the introduction of modern technology which would provide the possibility to diversify energy resources. The calculations confirm that the realised amount of thermal energy indirectly affects profit; directly it is affected by the rate of thermal energy, so the structure of use of energy in heat supply enterprises is associated with lowering the cost of (restrictive) factors - the energy cost, specific production technologies, energy efficiency. Currently, the primary condition of heating companies is to find such energy resource(s) to ensure the approved schedule of temperature and thermal load. The next determining factor is the energy price. In assessing the factors that will affect energy usage in the future, the main strategic principle of energy consumption will be linked to limiting the growth or even reducing heat tariff, by realising optimal efficiency and minimal environmental pollution during energy transmission.

Fuel as the main energy resource in agriculture and forest production is surveyed in the work. Specific weight of fuel and lubricants in applicable expenses in country farms is analysed, average fuel and oil consumption in farms of different specialization, as well as changes in oil price in farms of different size and specialization are shown.

Decrease of the consumption of energy resources is possible if grain is actively dry at low air temperatures, which also has a more favourable effect on a single grain. By using the new low-temperature technologies in grain drying, the same effect can be reached as by using grain dryers with high air heating temperatures. One of such technologies could be active drying of the grain layer at low air temperatures in ozone medium. Laboratory experiments show that the carried out moisture from grain is more efficient is active drying is performed using ozonized air. The presence of ozone in grain active drying process increases the amount of carried out moisture. Ozone when decaying to ordinary oxygen creates additional energy, which can be efficiently used in grain drying. As a result, grain drying is accelerated and energy consumption is decreased. Laboratory experiments prove the effectiveness of the presence of ozone in grain active drying process.

The energy-intensive timber industry enterprises have a significant role in Latvia’s manufacturing sector, contributing to the country’s sustainable economic development. They maintain the economic well-being of residents of Latvia’s rural regions and represent a substantial proportion of output value and export volume in the manufacturing sector and the state economy. Due to surging energy prices that negatively impact production costs, it is more difficult for enterprises to compete in foreign markets. The study aims to analyse energy consumption trends in timber industry enterprises in Latvia to propose activities for reducing energy costs, thus promoting the international competitiveness of timber industry enterprises. The analysis is based on data from Europe’s power market Nord Pool and databases of the Official Statistics Portal of Latvia. Methods used: statistical data analysis using time series analysis and expert interviews. The research results show that a significant threat to the competitiveness of enterprises is the increasing price of electricity, which is the second most consumed energy resource, accounting for nearly 15% of the total annual energy consumption of timber industry enterprises. To address high electricity costs, enterprises have the opportunity to install solar panels. Calculations show that, at an electricity price of 0.198 EUR per kWh, investments could lead to a five-year payback period with an ROI of 7.52%. At a lower electricity price of 0.13 EUR per kWh, the payback period would extend to ten years but still provide a reasonable ROI of 5.2%.