# Making Optimal Location-Sizing Decisions for Deploying Hybrid Renewable Energy at B&Bs
## 1 Introduction
Considering that visitors are more likely to stay at B&Bs than traditional hotels due to their authenticity [24; 25] and social interaction [26], B&Bs can collaborate with the entire community to offer novel experiences that leverage and integrate local resources [27]. Another interesting innovation is the increasing adoption of electric vehicles (EVs), which is expected to increase six-fold between 2019 and 2030 [28]. As pioneered by several hotel chains [29; 30], B&Bs can offer EV charging services at their facilities to proactively respond to market changes, generate new revenue streams, and develop more innovations. In terms of the internal conflict due to energy transition, B&Bs can take the opportunity of transgenerational ownership (succession from the old to the young generation). When the new management reevaluate their business strategy during this period [14; 31], this would be an ideal time to conduct an energy transition. A significant reduction in RE costs, even below 3.0 US cents/kWh in some countries [32], means it is also an ideal time for initiating the transition. Unfortunately, despite these opportunities, RE is still underutilized in the accommodation industry. For example, only 17.3% of hotels in the Asia-Pacific region have installed renewable energy generation devices (REGDs) [33]. The most common reason for not deploying RE at the accommodations is the personal belief of (high) upfront investment [34]. Compared to other accommodations, the lack of capital reserves [35] and heavy dependence on the power grid in most B&Bs [36] pose a challenge to a successful energy transition. Furthermore, there is a lack of know-how in initiating energy transition in accommodation businesses [34], mainly due to several complexities. B&Bs have to balance fluctuations in energy production and consumption due to the intermittent nature of most RE energy sources and the occurrence of peak demand at certain times. The hybrid RE system that combines two or more energy sources (e.g., solar and wind) can adequately manage these fluctuations [37]. However, a hybrid RE system, often equipped with batteries, increases the complexity of the problem compared to a single-source RE system. Further complexity arises from the variety of REGDs on the market,including conventional REGDs (e.g., solar panels and wind turbines) and unconventional REGDs (e.g., the Wind Tree). Both offer different tradeoffs that B&Bs must evaluate when transitioning to RE. B&Bs also need to manage the site availability since an installed RE system requires more land than a fossil power plant [38]. There is an urgent need for a decision-making framework to manage this complexity to ensure a resilient energy supply at an affordable cost. The decision should include the type and size of RE technologies for each suitable location on the B&B. According to the systematic review, the optimization approach provides good energy planning for ensuring sustainability [39]. Therefore, this study proposes a practical approach to address the critical need for all B&B businesses to make optimal decisions on deploying hybrid RE technologies in their locations. This study provides a model that integrates system components, including hybrid RE systems, batteries, the power grid, different ratios of self-sufficiency, and different RE technologies, to ensure a smooth energy transition. This integration provides B&Bs the flexibility to choose their preferred self-sufficiency as a target to be achieved by allocating a specific share of the energy demand to be met by RE and the rest by the power grid. In addition to bridging the gap between the high cost of RE technologies and the affordability of B&Bs, the model can also evaluate the tradeoff between conflicting goals, costs, and emissions when designing the system. This integration also assists the B&B in evaluating the tradeoff between conventional and/or unconventional REGDs and investigating the need to determine a specific size of batteries to regulate energy flow.