Swedish solar heated residential area with seasonal storage in rock: Initial evaluation

Improvement of borehole thermal energy storage design based on experimental and modelling results

“…Generally, spacing between 2.5 and 5 m are investigated [3]. However, other concerns such as maximum temperature increase in the storage volume or practical drilling conditions are to be considered to define the optimal distance between boreholes when designing a BTES.…”

“…The an optimal heat store design, more than 45 days would have been necessary for the temperature to recover its initial state after a long injection period (against six days in the experimental conditions as shown in Figure 2). Lundh & Dalenbäck [3] have stated that, as the Anneberg store is fairly small, the heat losses were assumed to reach 40 per cent. The dimensions of the DLSC system in Okotoks [4] and those of the Neckarsulm system [10] are close to the optimum ratio (D/h=2), and heat losses are reduced.…”

“…The design of an underground heat storage depends on the project context and designs are often developed on the basis of the results of numerical simulations. For example, Lundh & Dalenbäck [3] report that to select the most effective design for the Anneberg project given with an accuracy of 0.5°C. Geological and fracturing characteristics of the bedrock were determined by cutting analysis and geophysical techniques (long and short resistivity, natural gamma, bore-hole imagery, etc.).…”

Seasonal Thermal-Energy Storage: A Critical Review on BTES Systems, Modeling, and System Design for Higher System Efficiency

“…He and Lam demonstrate heating and cooling using a single system with energypiles in place of ground loop heat exchangers, simulated in TRNSYS [86]. The second type of system is the variety implemented at Drake Landing Solar Community (DLSC), featuring seasonal "charging" of the borehole with excess solar energy input to the ground [43,48,[87][88][89]. However, DLSC is unique in the fact that heating is provided by water to air heat exchange fan coils located in each home [43].…”

Modelling the Size of Seasonal Thermal Storage in the Solar District Heating System / Sezoninės Šilumos Akumuliacinės Talpyklos Tūrio Modeliavimas Centralizuotoje Saulės Šildymo Sistemoje

“…Švedijoje (Anenbergo mieste) įrengta požeminė 60 000 m 3 saugykla su 100 gręžinių kartu su 2400 m 2 saulės kolektorių plotu iš dalies padeda užtikrinti 50 gyvenamųjų pastatų šildymo poreikius. Šios saugyklos nustatyti šilumos nuostoliai sudaro apie 40 % (Lundh, dalenbäck 2008). Šveicarijoje atliktais tyrimais nustatyta, kad naudojant gręžinių saugyklas optimalus kolektorių plotas yra 2-4 m 2 /MWh metinio šilumos poreikio, o gręžinių tūris šiuo atveju sudaro 4-13 m 3 /m 2 kolektoriaus (pahud 2000).…”