16Given the increasing penetration of renewable energy technologies as distributed generation 17 embedded in the consumption centres, there is growing interest in energy storage systems 18 located very close to consumers. These systems allow to increase the amount of renewable 19 energy generation consumed locally, they provide opportunities for demand-side 20 management and help to decarbonise the electricity, heating and transport sectors. 21In this paper, the authors present an interdisciplinary review of community energy storage 22 (CES) with a focus on its potential role and challenges as a key element within the wider 23 energy system. The discussion includes: the whole spectrum of applications and 24 technologies with a strong emphasis on end user applications; techno-economic, 25 environmental and social assessments of CES; and an outlook on CES from the customer, 26 utility company and policy-maker perspectives. Currently, in general only traditional thermal 27 storage with water tanks is economically viable. However, CES is expected to offer new 28 opportunities for the energy transition since the community scale introduces several 29 advantages for electrochemical technologies such as batteries. Technical and economic 30 benefits over energy storage in single dwellings are driven by enhanced performance due to 31 less spiky community demand profile and economies of scale respectively. In addition, CES 32 brings new opportunities for citizen participation within communities and helps to increase 33 awareness of energy consumption and environmental impacts. 34

Measurements are reported of the effects of 0-23 mT applied magnetic fields on the spin-selective recombination of Py*- and DMA*+ radicals formed in the photochemical reaction of pyrene and N,N-dimethylaniline. Singlet <--> triplet interconversion in [Py*- DMA*+] radical pairs is probed by investigating combinations of fully protonated and fully deuterated reaction partners. Qualitatively, the experimental B1/2 values for the four isotopomeric radical pairs agree with predictions based on the Weller equation using known hyperfine coupling constants. The amplitude of the "low field effect" (LFE) correlates well with the ratio of effective hyperfine couplings, aDMA/aPy. An efficient method is introduced for calculating the spin evolution of [Py*- DMA*+] radical pairs containing a total of 18 spin-1/2 and spin-1 magnetic nuclei. Quantitative analysis of the magnetic field effects to obtain the radical re-encounter probability distribution f (t )-a highly ill-posed and underdetermined problem-is achieved by means of Tikhonov and maximum entropy regularization methods. The resulting f (t ) functions are very similar for the four isotopomeric radical pairs and have significant amplitude between 2 and 10 ns after the creation of the geminate radical pair. This interval reflects the time scale of re-encounters that are crucial for generating the magnetic field effect. Computer simulations of generalized radical pairs containing six spin-1/2 nuclei show that Weller's equation holds approximately only when the radical pair recombination rate is comparable to the two effective hyperfine couplings and that a substantial LFE requires, but is not guaranteed by, the condition that the two effective hyperfine couplings differ by more than a factor of 5. In contrast, for very slow recombination, essentially any radical pair should show a significant LFE.

No abstract

No abstract

PbA-acid and lithium-ion batteries are optimised up to a 100-home community. A 4-period real-time pricing and Economy 7 (2-period time-of-use) are compared. Li-ion batteries perform worse with Economy 7 for small communities and vice versa. The community approach reduced the levelised cost by 56% compared to a single home. Heat pumps reduced the levelised cost and increased the profitability of batteries.