## 1 Introduction
### Decarbonisation Strategy  
The regional government has recently published the PTECan-2030 (Plan de Transicion Energetica de Canarias), that establishes a roadmap to decarbonise the Canarian energy system. This main objective is divided into several specific objectives: energy autonomy, decarbonisation of the economy, electrification of heat/cooling and transport demands, as well as progressing in circular economy approaches. Although the PTECan plan envisages a full decarbonisation of the economy in 2040, only domestic-specific goals are set for 2030, described as follows:  
* A 62% share of RE in the generated electricity. * A 29% of RE share in the total final energy consumption. * A 27% of energy efficiency improvement. The PTECan plan does rely on a series of specific studies covering aspects such as net metering potential [43], energy storage [44], transport electrification [45], future dispatchable power generation [46], or the deployment of H\({}_{2}\) as fuel [47]. An in-depth analysis of future energy demands and transport evolution was performed as a basis to propose the suitable energy system structure subjected to a series of identified constraints. With respect to the power-generation sector, the plan for Tenerife proposes a massive deployment of renewable sources in the 2025-2040 timeline. From the current value of 333 MW, the strategy suggests that RE capacity will be increased by approximately 14 times, as Table 3 depicts. In this context, PV, both self-consumption and utility scale, would experience a significant growth, with 2302 MW. The plan also relies on increasing the on-shore WE capacity by 7.5 times, by means of installing new units and re-powering the old ones. Off-shore WE will also play a key role in the future energy mix, as the plan expects 505 MW. To a lesser extent, geothermal and wave energy will also be introduced in the energy system, with 20 MW and 5 MW, respectively. The plan also points out the need for 210 MW of firm generation provided by gas turbines, using internally generated H\({}_{2}\) from renewable sources. Although the PTECan-2030 lacks clarification regarding the energy storage systems (ESSs) for the island of Tenerife, the specific strategy supporting the plan does rely on a significant deployment of user-based EES (batteries) accompanying the expected massive penetration of self-consumption PV. Up to 2.5 GWh of available EES is expected, allowing higher rates of PV share in the power-generation mix. Distributed EES, located across the different electricity substations, could also reach the significant figure of 1.1 GWh. The space constraints and the orography of the island limit the deployment of large-scale energy storage systems, such as pumped storage hydropower, compressed-air energy storage or Liquid Air Energy Storage. Multiple assessments regarding plant locations \begin{table}
\begin{tabular}{l c c} \hline \hline  & **LDV Energy Consumption [TWh]** & **HDV Energy Consumption [TWh]** \\ \hline Petrol & 2.52 & - \\ Diesel & 1.21 & 2.03 \\ Total & 3.73 & 2.03 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Oil-based annual energy consumption of road transportation. have been conducted [44]. Current projections suggest 300 MW/4800 MWh of maximum capacity for this kind of system. Any additional energy storage requirements will be covered by batteries. From PTECan's perspective, BEVs will be the dominant technology across the light-duty transport sector. From the current low figures of a 12% share in new registrations, BEVs will progressively take the place of ICEs until the total abandonment of fossil fuels. In the context of the heavy-duty transport sector, Fuel Cell Electric Vehicles (FCEVs) will be the major technology to replace the diesel fleet. Although the work behind the aforementioned strategies has been extensive and covers the entire period until decarbonisation, the final PTECan plan, which is a combination of the most relevant outcomes, lacks clarity defining the future energy demands and technology deployment beyond 2030.