The space under the afterdeck houses the engine. It is a Barrus "Shire 45", common in both hire and private boats.
A bank of 5 x 110aH batteries supplies the 12v DC circuit, also driving a 3kW inverter for 240v AC 'mains'. A separate battery is provided for starting the engine (in case one runs the domestic batteries flat), and for the bowthrust unit. Batteries are charged from the engine whilst running, or from shore power when hooked up. There is also a solar panel.
The engine cooling system can route the waste heat to the central heating system. When the engine is not running, there is a diesel-fired heating system. Both these also heat the domestic hot water. When heating is not required, there is an immersion heater for the hot water, but either the engine must be running or the boat on shore power as the elecric drain is very high.
Due to the shape of the stern (the underwater shape tapers to a point, where the above-water hull is curved), there are "shelves" at each side of the engine. These house the batteries and provide some storage space.