B-B-Blimey, does your neighbour have Raynaud's Disease or something similar? That's a ridiculous amount of wood
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If Greek houses are anything like Italian ones then insulation will be non-existent: changing doors and windows has made a huge difference to our house. Also, most Italians use spectacularly inefficient built-in stoves with built-in boilers or open fires with windows and doors left open. Before overhauling your heating system look at areas where you can improve insulation.
Here in southern Italy, which can have either cold or very wet winters, the prunings from just six secular olive trees provides enough for wood for all our heat, hot water and cooking in the winter as well as for the BBQ and pizza oven in the summer. We have a back boiler on our woodburner (6kw with 2.9kW backboiler). This heats a couple of radiators too. We'd been told by experts that our stove was way too small, but the house is toasty in the winter, much to the relief of a Christmas visitor from London who has both Raynard's Disease and central heating. She said our house was warmer than her flat.
We have a solar panel too, but while it provides enough hot water for a shower or two in the winter it's nowhere near warm enough to heat the house. If it's cold during the day we'll light a range cooker.
If it's bedrooms, which are cold I'd recommend getting an efficient electric blanket and put it on for half an hour before you go to bed and switch it off when you retire for the night. If you shop around and get a good one it will only cost a cent or two per use.
