Energy packet networks: smart electricity storage to meet surges in demand

When renewable energy is used either as a primary source, or as a back-up source to meet excess demand, energy storage becomes very useful. Simple examples of energy storage units include electric car batteries and uninterruptible power supplies. More sophisticated examples include dams into which water may be pumped when renewable sources of electricity such as wind or photovoltaic are plentiful. Drawing an analogy between computer networks which store and forward and download data, and electrical networks that furnish energy both from direct production and storage, we suggest a model of Energy Packet Networks (EPNs) which store and forward quantised energy units to and from a large range of devices. In addition to being a model for networks of energy storage units, energy suppliers and consumers, an EPN can be an appropriate framework for energy harvesting networks at the micro-scale, and bio-nano scale energy networks. A mathematical model for EPNs is suggested and we analyse two examples using a probability model. We first consider the case where stored energy and a fast ramp-up source are used to meet random energy surges assuming an unlimited storage unit and a random flow of renewable energy, and compute the probability that all requests are satisfied, or that some cannot be satisfied, and the spillover rate of renewable energy. Then we analyse the effect of an imperfect communication and computer-control system where message losses and delays degrade the energy system performance.