Dagnija Blumberga

Riga Technical University | RTU · Institute of Energy Systems and Environment

To recover thermal energy from different sources, its quality and possibilities for utilisation are essential. The wide range of engineering solutions includes a direct connection to the district heating (DH) system and the integration of low-quality heat using heat pumps to increase the temperature level of recoverable heat. Therefore, this articl...

Increasing renewable energy share in total energy production is a direction that leads toward the European Union’s aims of carbon neutrality by 2050, as well as increasing energy self-sufficiency and independence. Some of the main challenges to increasing renewable energy share while providing an efficient and secure energy supply are related to th...

Decentralized electricity production at household scale, particularly by solar panels, has recently grown due to increased technology feasibility and financial support programs. Further development in this field requires the introduction and efficient use of energy storage technologies. This research aims to evaluate the benefits and economic justi...

The EU power sector is under increasing pressure due to rising electricity demand and the need to meet decarbonisation targets. Member states have been active in investing in renewables and building capacity to increase their share of renewables in electricity generation. However, it is important to examine what progress each member state has made...

Energy consumption across industries accounts for more than seventy-five per cent of total greenhouse gas emissions in the European Union. Energy is a top priority for achieving climate goals and low greenhouse gas emission levels. The comparison of sustainable development pat-terns in renewable energy sources is carried out for all the different s...

Fish is an inexpensive source of high-quality protein as well as valuable micronutrients. Increasing the volume of fish and producing more fish feed is necessary to ensure the necessary consumption. One of the main components of fish feed is oil, the most crucial lipid source in fish feed. Fish oil is easily digestible and contains essential fatty...

The agricultural sector’s progress toward climate neutrality is of great importance not only in the climate, but also in economic and social contexts. Climate-neutral agriculture is highly dependent on innovations that ensure maximum efficient farming, which not only reduces emissions but also ensures competitiveness in the market; all of this is f...

Sustainable development in the agriculture sector can be boosted by integrating a sustainable bioeconomy and transforming renewable resources into added-value products. There are various methods to determine, measure, and compare the extent of sustainability. We promote the bioeconomy concept by utilizing agricultural waste in biopolymers consideri...

A vital component of achieving climate neutrality in the future involves bolstering energy efficiency measures in educational institutions and improving the overall knowledge on sustainable solutions. To achieve fruitful outcomes, the active involvement of various stakeholders, such as managers, teaching staff, and students, is indispensable. By im...

The share of renewable energy in heat and power generation is expected to increase significantly and reach record levels in the coming decades. As a result, emerging energy storage technologies will be key elements in balancing the energy system. To compensate the variability and non-controllability of seasonally generated renewable energy (RES) (d...

The pace of the implementation of renewable electricity storage in Europe is disappointingly slow. Several factors influence this and there is a need to speed up the rate and increase the volumes in order to promote a 100% transition to renewable energy resources, expand the practice of using renewable energy, and contribute to the improvement of t...

Innovative pricing mechanisms should motivate heat suppliers and consumers to move toward more sustainable energy systems and introduce low-temperature district heating systems and sector coupling in smart energy systems. Therefore, district heating regulation regimes should also be changed to stimulate transformations in the energy sector. The dis...

The agricultural sector's progress towards climate neutrality is of great importance not only in the climate but also in the economic and social context. The agricultural sector is the 3rd largest emission-generating sector both in Latvia and Europe, and it directly and/or indirectly affects all other sectors. Climate-neutral agriculture is highly...

The marketability of fish depends on the visual appearance of the fish, so the feed ingredient pigment contributes to the nutritional value and visual appearance of the product. The benefits of a natural pigment derived from microalgae are the ecological benefits, as the culture can fix carbon and release oxygen. The economic aspect is a benefit of...

Global annual textile consumption has doubled in the last two decades and is expected to keep increasing. Since the textile system operates primarily in a linear way, it is highly polluting and creates a lot of waste. But nevertheless, it has a high potential for circularity since most textile products can be recycled or reused. Today most of the w...

With global energy demand rising and climate change targets becoming more ambitious, the use of biomass for combustion will become even more important than it already is. As wood supplies become scarce, leading to increased demand for materials and energy, the demand for alternative solid biofuels for energy use is growing. Using various biobased r...

Carbon neutrality in municipalities can be achieved by combining individual heating and district heating solutions involving the use of renewable energy sources. Each approach has advantages and disadvantages, but the best solution depends on the specific circumstances of each municipality. As an environmentally friendly and efficient energy use, a...

The research identifies and describes administrative procedures for implementing RES electricity generation infrastructure projects in Baltic and Nordic countries. The administrative processes of installing small to large solar parks and onshore wind farms for electricity generation were assessed, looking at several criteria such as the timeline, c...

The pace of implementation of renewable electricity storage in Europe is disappointingly slow. Several factors influence it, but there is a need to speed up the rate and increase the volumes in order to promote a 100% transition to renewable energy resources, expand the practice of using renewable energy, and contribute to the improvement of the us...

The share of renewable energy in heat and power generation is expected to increase significantly and reach record levels in the coming decades. As a result, emerging energy storage technologies will be key elements in balancing the energy system. Compared to power generation technologies, storage technologies are considered one of the most complica...

The pace of implementation of renewable electricity storage in Europe is disappointingly slow due to several factors. There is a need to speed up the rate and increase the volumes in order to promote a 100 % transition to renewable energy resources, expand the practice of using renewable energy, and contribute to the improvement of the user’s quali...

This research combines the analysis of international knowledge in energy audit practices with information on the nature of energy audit and its involved parties on the path to fulfil the goals set by the European Union policy and Latvian national policy. The article also analyses the publicly available information about the energy sector in Latvia,...

The review examines in detail the types of factors that may influence residents’ motivation to implement energy efficiency measures in multifamily housing. When analyzing heating energy consumption in multi-apartment buildings, three influencing factors must be considered: the condition of the building, technology-based solutions, and occupant beha...

To achieve the climate targets set by 2030 and become climate neutral by 2050, each Member State must develop a National Energy and Climate Plan (hereinafter NECP) containing practical and effective measures to achieve the targets. The research sought a connection between the measures or action lines in the Latvian NECP related to agriculture and f...

Promoting sustainability in educational systems is crucial for preserving resources and diminishing negative impacts on the environment. A key aspect of this is enhancing energy efficiency within educational institutions. By implementing energy-efficient building systems, advancing the use of renewable energy sources, and incorporating sustainable...

The urban heat island (UHI) phenomenon has differential impacts on energy use and carbon emissions in buildings depending on the climate of the region and the urban planning strategies in place. This study explores the differential effects of UHI on energy use and carbon emissions in warm and cold climates, using North Africa and North Europe as ca...

To achieve the set climate targets by 2030 and become climate neutral by 2050, each Member State must develop a National Energy and Climate Plan (hereinafter – NECP) that contains practical and effective measures to achieve the targets set. The effectiveness of the agricultural and forestry measures defined in the Latvian NECP was assessed through...

Sustainable development in the agriculture sector can be boosted by integrating a sustainable bioeconomy and transforming renewable resources into added-value products. There are various methods to determine, measure, and compare the extent of sustainability. We promote the bioeconomy concept by utilizing agricultural waste in biopolymers consideri...

The publication examines what measures the European Union is currently taking in the energy sector to promote energy security and independence from fossil energy resources. Taking into account the geopolitical situation, the European Commission has launched REPower – a new action plan for Europe on how to save energy, diversify energy supply and us...

Global annual textile consumption has doubled in the last two decades and is expected to keep increasing [1]. Since the textile system operates primarily in a linear way, it is highly polluting and creates a lot of waste. But nevertheless, it has a high potential for circularity since most textile products can be recycled or reused. Today most of t...

Energy consumption in different sectors is responsible for more than 75 % of total EU greenhouse gas emissions. Energy is a priority when it comes to achieving climate goals and keeping greenhouse gas emissions low. The Green Deal is based on the need to use renewable energy sources in the energy sector while ensuring the replacement of fossil fuel...

As the consumption of fish in the human diet increases, a larger amount of production is needed. The growing demand for fish also has an impact on fish feed, its production efficiency and the sustainability of using raw materials. To evaluate the sustainability of raw materials and the impact on the environment, three protein alternatives are compa...

To achieve the goals of the bioeconomy, formal education is a cornerstone, as well as non-formal or lifelong learning and informal education. Professionals in their specific profession can expand their knowledge in the context of bioeconomy in non-formal education by attending various seminars and courses, acquiring knowledge in informal or self-ed...

Climate change, rising food and feed demand, and biodiversity loss necessitate a more sustainable, innovative, and knowledge-based bioeconomy. This research analysed and compiled statistical data, reports, and other official information from Latvian forest sector stakeholders to understand its system components. After identifying main enablers and...

The growing demand for fish and the development of the industry raise concerns about environmental impact. As fish production increases, so does the consumption of fish feed. One of the ingredients in fish feed is pigment, which improves the nutritional value and visual appearance of the product, increasing their marketability. Astaxanthin is a red...

Carbon-neutrality in municipalities can be achieved by combining individual heating (IH) and district heating (DH) solutions involving the use of renewable energy sources (RES). Each approach has advantages and disadvantages, but the best solution depends on the specific circumstances of each municipality. As an environmentally friendly and efficie...

Mitigation of CO2 emissions has become a top question in international and national arenas, likewise on the city level. Existing CO2 mitigation measures are primarily orientated toward wider deployment of low-carbon technologies of renewable energy sources and energy efficiency measures, focusing on energy production, distribution, and energy use s...

Currently, the use of heat pumps in the Republic of Kazakhstan is becoming popular. However, there is no introduction of low-potential thermal resources from renewable sources together with the use of heat pumps, which is important in the area of energy conservation and also deemed nature-friendly for the country. The purpose of this work to form a...

Greenhouse gas (GHG) emissions are declining in all major sectors in the European Union, with the exception of one sector that has seen a significant increase in GHG emissions over the past decade-transport sector. The European transport sector faces a significant challenge in achieving the decarbonization goal set by the European Green Deal. Altho...

The broad spectrum of bioresource use makes it challenging to interconnect strategic objectives and policy planning documents without compromising a coherent development vision. Bioeconomy development directions have been defined at the EU and Latvian levels. Nevertheless, to facilitate their implementation, the goals must be consistent with those...

Latvia’s wood industry is based mainly on three product groups – fuelwood, wood-based panels and furniture. This research adopts the TIMES modelling approach to assess the potential of forestry resources’ contribution to the development of bioeconomy by evaluating different existing and new products. The modelling approach is commonly used for ener...

There is no one unique parameter with value which can represent bioeconomy sustainability and development. However, many different parameters can be used to describe the economic, social, environmental technological aspects of bioeconomy. The paper present combined approach with using multi criteria decision analysis (MCDA) and fuzzy cognitive map...

At the end of 2019, the European Commission launched a new growth strategy called ‘The European Green Deal’ (GD), which aims to ‘transform the European Union (EU) into a fair and prosperous society with a modern, resource-efficient a competitive economy with no net greenhouse gas emissions in 2050 and where economic growth is decoupled from resourc...

Valorization of CO2 captured from industrial processes is an important task for reaching climate and energy targets. The presented study addresses the use of CO2 for the production of ethanol, which can be used as a transport fuel. Hydrogen, produced by renewable energy technologies, is combined with CO2 to produce the synthetic fuel, thus making t...

The future of sustainable development is the bioeconomy with both global and local renewable energy solutions. The updated Bioeconomy Strategy and the Green Deal serves as prove of European Commission commitment for transformation towards a sustainable and climate-neutral European Union. This process is characterized with an enormous complexity and...

The household sector has a significant role in the consumption of energy resources and related emissions. The household sector is responsible for around 1/3 of the total energy resource consumption in Latvia. This study aims to determine the level of control measures regarding household boilers by summarising the existing information on legislation...

The last decade in particular has seen prosperity in global challenges. Traditional industry leaders have to compete with the challenges of the new generation in emerging markets. Although the European market is competitively mature, the prosperity in global challenges makes it necessary to defend the domestic market as well as to pursue growth opp...

Woody logging residues produced by logging activities are currently an underutilised resource that is mainly burned for energy production or left in the forest to decay, thus releasing CO 2 into the atmosphere. This resource could be used to manufacture long-lasting products and store a significant amount of CO 2 , promoting CO 2 valorisation in ru...

100 cities in Europe have committed to being pioneers and achieving climate neutrality by 2030. It is crucial to start with the decarbonization of cities because, although they cover only 3 % of the Earth’s land, they produce 72 % of all greenhouse gas emissions. This paper contributes to the city decarbonization research but on a smaller scale. We...

Yeast Single-Cell Proteins (SCP) production using various agro-industrial byproducts and wastes have significant potential as an alternative to the soy meal, and fish meal protein used for livestock and aquaculture feeds. The use of organic wastes as a substrate in the fermentation processes can be accepted as one of the solutions to reduce the tot...

In the light of the Green Deal and its ‘Farm to Fork’ and ‘Biodiversity’ strategies, the EU aims to find new ways to decrease GHG emissions through the EU Carbon Farming initiative stating that farming practices that remove CO 2 from the atmosphere should be rewarded in line with the development of new EU business models. The Carbon farming initiat...

Reed biomass is a widespread resource available in large quantities all over the world, it is fast growing, there is no need for cultivation, harvesting and use des not compete with any other industries. Despite all this, reed is still not widely used and many potential use alternatives have not been researched. Therefore, the aim of this study was...

As the population grows, demand for food increases. Fish is considered to be one of the most efficient sources of protein. But as demand increases, we need to think about the efficient and sustainable fish feed. There is a need to replace existing feed ingredients such as fishmeal and fish oil with more sustainable sources of protein and oil. In 19...

The rapid consumption of resources, as well as the increase in the number of people, has raised awareness of the urgent need to change Europe’s existing methods and attitudes towards the consumption of biological resources in production, processing, storage, reuse and disposal. One of the key principles of the European Green Deal is to make the EU...

As food consumption increases, so does the number of agricultural by-products. That is why it is necessary to find the best possible uses for them, operating by the principles of the bioeconomy. This work aims to gather information on the possibilities of using grain byproducts to develop new products and evaluate which bran products are the most s...

Climate change poses a major challenge to capitalist-oriented societies to restructure their economies and adapt to low-carbon measures that, at first glance, may not be the most economically viable option. Therefore, climate-economy models have become increasingly important in environmental and energy policy in recent years. This study examines re...

The European Green Deal sets an ambitious target for Europe to reach climate neutrality by 2050. This commitment will be a challenge, particularly in the context of agriculture, as the sector is responsible for sustainable development and food security. However, one of the primary sources of GHG emissions from the agricultural sector is the treatme...

The bioeconomy policies and sustainable development goals are a more focused area in the past few years due to their increasing significance in every sector. This research contributes to developing a better bioeconomy strategy concerning its Sustainability within the agricultural biorefinery sector by reviewing the bioeconomy modeling tools. A revi...

Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution increases due to hostile human activities. The sustainable way to utilize agricultural waste and promote the bioeconomy concept is to produce an alternative product of plastic, i.e., ‘bioplastic’. This paper used different keywords to perform the bibli...

The article presents the types and classification of waste from the phosphorus industry of the Zhambyl region of the Republic of Kazakhstan. Waste is classified by its use as recyclable materials for construction materials. The results of a comparative assessment of the physical, chemical and structural properties of the phosphorus industry waste a...

Evolving complex concepts, such as bioeconomy, in the most effective way, can be applied through the education of students and professionals. In recent years changes in the education system can be observed with the development of knowledge-based learning. Competence-based learning will also be used more and more in higher education. Higher educatio...