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This paper is concerned with electrically heated asphalt pavements; it numerically explores the possibility of such technology to actively suppress frost penetration under seasonal cold-weather conditions. A thermal model is outlined for the investigation based on the one-dimensional heat equation including latent heat effects. This model is applied to a multilayer medium containing a buried heat source representing the heating system. Utilizing cold-climate weather data from northern Finland, calculations were performed to track the evolution of the frost front depth in an idealized pavement structure with no heating. Then the model calculations were repeated with the heating activated. A parametric study was performed with different heat production intensities and several embedment depths for the heating system. It is numerically demonstrated that embedded electrical heating can suppress frost penetration depth and duration in asphalt pavements, rendering the explored application practically feasible. [ABSTRACT FROM AUTHOR]

Distributed electric power production by small-scale customers is increasing continuously. Photovoltaic production is a popular method of producing self-energy for customers. Additionally, power systems require more flexibility when weather-dependent renewable energy production increases. Small-scale customers can increase the self-consumption of self-produced energy by using batteries or a demand response operation. However, batteries require high investment, and demand response operations induce a loss of comfort. Customers who heat their buildings using electric heaters are a good target for demand response operations because their heating can be controlled with limited changes in the indoor temperature. The demand response potential of a building can be defined by simply using customer load profiles and knowledge of the outdoor temperature. Any other information is not required in the proposed novel method. A tolerable variation in indoor temperature corresponds to considerably smaller battery capacity, though it is still a significant amount. With an optimally sized photovoltaic system, it is possible to use both methods simultaneously to increase self-consumption. Maximal benefits can be attained from both methods if the battery system is used as a primary control and the demand response is used as a secondary control. The defined novel method for determining the demand response potential of small-scale customers can also be used when estimating the flexibility of a large customer group. Small-scale customers together can provide significant flexible capacity when their electrical heating is centrally controlled. [ABSTRACT FROM AUTHOR]

Unexpected power outages and extreme weather encouraged research on energy-resilient buildings throughout the world. Resilient building research mainly focuses on hot weather rather than cold extremes. This study defines resilience terminologies based on the available literature and discusses the impact of energy efficiency on energy resilience performance in energy-efficient buildings due to abrupt power outages in an extremely cold climate. The assessment involves the case simulation of a multistory apartment located in southern Finland at design outdoor conditions (−26 °C) in IDA-ICE 4.8, a dynamic building simulation software, and its techno-economic assessment to ensure building resilience for up to 7 days of power outages. The assessment shows the efficient building envelope can enhance the time taken by the building to drop the indoor temperature to the threshold by approximately 15%. Additionally, the efficient heating system along with the building envelope can reduce the instantaneous power demand by up to 5.3 times, peak power demand by up to 3.5 times, and on average power consumption by 3.9 times. Similarly, the study finds that the total energy requirement during a blackout can be reduced by 4.1 times. The study concludes that enhanced building resilience is associated with energy-efficient parameters such as an efficient energy system and an efficient building envelope that has low thermal losses and high thermal inertia retention. The batteries contribute the maximum proportion to the overall retrofitting cost, and the proportion can go up to 70% in baseline configurations and 77% in efficient configurations of buildings. The analysis concludes that the required investment varies largely with the technologies involved and the combination of components of these energy systems. The assessment finds that the high investment costs associated with batteries and battery recharging costs are the main bottlenecks to feasible flexibility in market participation. [ABSTRACT FROM AUTHOR]

The city of Tampere in Finland aims to be carbon-neutral in 2030 and wanted to find out how the electrification of public transport would help achieve the climate goal. Research has covered topics related to electric buses, ranging from battery technologies to lifecycle assessment and cost analysis. However, less is known about electric city buses' performance in cold climatic zones. This study collected and analysed weather and electric city bus data to understand the effects of temperature and weather conditions on the electric buses' efficiency. Data were collected from four battery-electric buses and one hybrid bus as a reference. The buses were fast-charged at the market and slow-charged at the depot. The test route ran downtown. The study finds that the average energy consumption of the buses during winter was 40–45% higher than in summer (kWh/km). The effect of cabin cooling is minor compared to the cabin heating energy needs. The study also finds that infrastructure needs to have enough safety margins in case of faults and additional energy consumption in harsh weather conditions. In addition, appropriate training for operators, maintenance and other personnel is needed to avoid disturbances caused by charging and excessive energy consumption by driving style. [ABSTRACT FROM AUTHOR]

Data center industry is growing rapidly due to the expanding internet traffic and the upcoming IoT revolution. Data centers consume vast amounts of energy globally and are also a significant source of greenhouse gas emissions. There is a need to improve energy efficiency and sustainability of data center operations. The energy consumed by data centers is mostly converted to heat and this study focuses on utilizing that waste heat according to the principles of circular economy in the context of Northern Ostrobothnia, Finland. The overall regional business potential of data center waste heat utilization is evaluated and the best options of utilizing waste heat in case data center are sought. The study found that the most viable option would be utilizing waste heat locally to heat facilities or in industrial processes. Another potential option is to connect data center into a district heating system where waste heat can be fed. [ABSTRACT FROM AUTHOR]

Fuel-operated auxiliary heaters (AHs) can be notable sources of particle emissions from vehicles. The emissions of AHs are unregulated, and the number of devices is high; therefore, they make considerable contributions to local air quality, and even the global emissions budget. Experiments for studying the emissions were performed in Finland for a total of eight selected vehicles with Original Equipment Manufacturer (OEM) AHs installed, including both diesel- and gasoline-operated heaters. We present the numerical results of particle emissions and compare the particle concentrations in the AH exhaust to values found in the tailpipe exhaust of the same vehicle. Our results show that the emissions from auxiliary heaters are typically several orders of magnitude higher than of a car exhaust when idling. This raises the question of whether the use of heaters is justified based on the goal to reduce total emissions from vehicle use; furthermore, whether fuel-operated heaters should also be applied in electric vehicles for cabin heating. More research will be needed to characterize the emissions more thoroughly to understand the air quality and climate effects from AHs, and to provide further recommendations on the use of these heaters. [ABSTRACT FROM AUTHOR]

In Finland, old apartments (1980s) contribute toward emissions. The objective is to reduce CO2 emissions to reach Europe's targets of 2050. Three different centralized solar-based district heating systems integrated either with non-renovated or renovated old buildings in the community were simulated and compared against the reference city-level district heating system. The three proposed centralized systems were: Case 1: photovoltaic (PV) with a ground source heat pump (GSHP); Case 2: PV with an air-water heat pump (A2WHP); and Case 3: PV with A2WHPs, seasonal storage, and GSHPs. TRNSYS simulation software was used for dynamic simulation of the systems. Life cycle cost (LCC), CO2 emissions and purchased electricity were calculated and compared. The results show that the community-level district heating system (Case 3) outperformed Case 1, Case 2, and the city-level district heating. With non-renovated buildings, the relative emissions reduction was 83% when the reference energy system was replaced with Case 3 and the emissions reduction cost was 3.74 €/kg.CO2/yr. The relative emissions reduction was 91% when the buildings were deep renovated and integrated with Case 3 when compared to the reference system with non-renovated buildings and the emission reduction cost was 11.9 €/kg.CO2/yr. Such district heating systems could help in meeting Europe's emissions target for 2050. [ABSTRACT FROM AUTHOR]