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Increasing the attractiveness of district heating networks to consumers

This report has been established within the Flexiheat project. Flexiheat has focused on increasing flexibility in district heating systems. The intelligent district heating network is a dynamic network: an open network where different waste heat and renewable energy sources are connected, that has multiple producers and groups of consumers and facilitates the connection between different energy infrastructures (gas, heat and electricity). Eventually this will lead to an optimal deployment of the available heat sources and an increased cost-efficiency of district heating. Flexiheat aims to develop new concepts for these intelligent, flexible district heating networks. One of the strategies is to allow third party access to the network. A smart control system is developed to manage the heat flows across the network. This system makes use of dynamic pricing. In this exploration the concept of third party access in relation to the Flexiheat project will be discussed. The development of new business and price models based on the Flexiheat approach has led to an analysis of possible alternative price models for consumers.

Moses Health Monitoring system for Firefighters

When firefighting, the combination of exposition to high temperatures, high physical demands and wearing (heavy and insulated) personal protective equipment lead to increased risk of heat stress and exhaustion in firefighters. Heat stress can easily evolve into a life-threatening heat stroke. Once heat stress occurred, the chance of getting another heat stroke during deployment gets higher. Moreover, intermittent exposure to heat stress over several years, is a risk factor for heart diseases. Similarly, exhausted during a deployment, a firefighter needs more time to rehabilitate before he can safely be deployed again. Heat stress and exhaustion can lead to line-of-duty cardiovascular events. Therefore preventing heat stress and exhaustion during deployment is beneficial for health, functioning and employability of firefighters. Since currently available measurement of the core temperature, such as thermometer pill or neck patch thermometer, are not reliable or practical for firefighters, an alternative approach may be used, namely, estimation of the core temperature based on non-invasive observation of the heart rate. Exhaustion is estimated using the training impulse model based on the heart rate reserve. Our achievement is a MoSeS health monitor system (as a smartphone application) that can real time analyze the health status of a firefighter and predict exhaustion and heat stress during deployment. The system is cheap (only a heart rate sensor and a smartphone application is needed), easy to use (intuitive “traffic light” signal), and objective (the health status is determined based on measurements of the heart rate). The only restriction is that the developed model is strongly dependent on personal maximum and minimum heart rate which need to be established behforehand. Moses Health Monitoring system for Firefighters CC BY-NC-ND Conference Proceedings 17th international e-SOCIETY 2019 IADIS

Thermo-staat

The Thermostaat project aimed to investigate how can we use community creation and citizen science to make people more aware of and more adapted to heat in apartments as a consequence of climate change. To this end, residents in IJmuiden and Amsterdam measured temperature in their apartments and with the help of the researchers reflected on their situation and heat adaptation options. Investigative journalists working in this project then brought the stories of the residents to the general public.

The impacts of the thermal radiation field on thermal comfort, energy consumption and control

Thermal comfort is determined by the combined effect of the six thermal comfort parameters: temperature, air moisture content, thermal radiation, air relative velocity, personal activity and clothing level as formulated by Fanger through his double heat balance equations. In conventional air conditioning systems, air temperature is the parameter that is normally controlled whilst others are assumed to have values within the specified ranges at the design stage. In Fanger’s double heat balance equation, thermal radiation factor appears as the mean radiant temperature (MRT), however, its impact on thermal comfort is often ignored. This paper discusses the impacts of the thermal radiation field which takes the forms of mean radiant temperature and radiation asymmetry on thermal comfort, building energy consumption and air-conditioning control. Several conditions and applications in which the effects of mean radiant temperature and radiation asymmetry cannot be ignored are discussed. Several misinterpretations that arise from the formula relating mean radiant temperature and the operative temperature are highlighted, coupled with a discussion on the lack of reliable and affordable devices that measure this parameter. The usefulness of the concept of the operative temperature as a measure of combined effect of mean radiant and air temperatures on occupant’s thermal comfort is critically questioned, especially in relation to the control strategy based on this derived parameter. Examples of systems which deliver comfort using thermal radiation are presented. Finally, the paper presents various options that need to be considered in the efforts to mitigate the impacts of the thermal radiant field on the occupants’ thermal comfort and building energy consumption.

Human whole body cold adaptation.

Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold.

Thermal comfort in urban green spaces: a survey on a Dutch university campus.