Conclusion

First of all, it is important to mention that all this study is highly influenced by the occupancy and the different behaviour that people could have when staying in a holiday community. Any change in the trend of the people enjoying a holiday in this type of accommodation affect the energy demand.

Based on the supply-demand matching results we can conclude that it could be feasible to achieve a Zero Carbon and Autonomous Holiday Community in Craik although it will not be efficient.

According to our results, one option could be to install the proposed Small Scale Biomass CHP running at 100% of capacity and at constant load throughout the year and another option could be to install it running at 25% of capacity, switching it on and off according to the thermal demand and adding hot water storage, PV panels and batteries.

However, in both cases we would have energy surplus. The thermal and electrical surplus of the first case is huge. Although the second case would have only electrical surplus and it would be lower than in the first option, it will still be high.

Thus, it will be necessary to deal with the energy surplus according to the selected system. Having taken into account the location and structure of Craik's project, some suggestions have been found.

For the thermal surplus:

Greenhouses could be built for the community benefit. These greenhouses would be supplied with the extra heat available and they could be used in two different ways. Firstly, some orchards could be created in order to supply food to the community and sell the goods in the shops of the Commercial Area (Courtyard Development) having in this way some profit. Moreover, the overall embodied energy of the project would be reduced due to the fuel saved in transporting the food from the supplier until the site. Another interesting option could be to explore the possibility of creating algae farms in these greenhouses in order to obtain bio-fuel that could be sold or used on site if required
Surplus heat could be supplied to the local households in the nearby village. In this way, objections of local people regarding the creation of a holiday community in the middle of the Craik Forest could be reconsidered.
An indoor swimming pool could be built. This could be used as a heated pool for recreational purposes. This solution could extend the pool usage period if an insulating pool cover is also used. Water itself behaves like a thermal sink for dumping extra-generated heat from small-scale biomass CHP. It could be also explored the option of using the swimming pool as a big storage tank.

For the electrical surplus:

Regarding the electrical surplus, a detailed analysis of the possibility of upgrading the grid should be carried out in order to assess the viability of exporting the additional electricity generated. If Craik project could not be connected to the grid, some suggestions about the possible use of this electricity would be the following:

First of all we should take into account that some surplus should be used in some communal facilities as the streetlights of the site or the Biomass CHP Plant.
Also it could be sent to local households of Craik village
If in the future, after building all the phases the electricity surplus would be large, it would be possible to think of creating an electric vehicle charging station which could support faster charging at higher voltages and currents than are available from domestic supplies if the electrical vehicles become to be more established. It could influence positively in the recognition of Craik as an authentic site which totally respect the environment.

Summarizing, it would be more feasible and more energy efficient if more than 6 houses are built in the 1st phase. However, it would be difficult to predict the exact number of households needed to be built in order to achieve the best efficiency due to the more houses we have, the more strategies we could follow in order to supply the energy. For instance, if the number of households were large enough, it would be possible to have two Biomass CHP running at the same time, one running at constant capacity covering the basic load and the other following the peaks. Moreover, it is necessary to realise that, the main problem in terms of surplus happen when there is no people at all in the Holiday Accommodation, as it occurs for instance in some days of February, when there is no energy demand and the Biomass CHP, if it is running at constant capacity, is producing energy. Then, if the Holiday Community had more than households available, the possibility of having guests more equally distributed along the month would be high and hence the surplus would be low.

Finally, it should be underlined that the general applicability of this project could be to apply this methodology to similar eco-tourism accommodation and to remote and off-grid island communities.