ZENduurzaam.nl offers a direct link with the sustainable energy systems ZEN Renewables:
Solar (hot water), Solar (green electricity) and Heat (living environment with soil energy).

I've been a little while looking for a suitable combination of an air heat pump, solar and solar system. That's how I met Zen Renewables (see link and quote above). I will soon have a quotation. The ground heat pump costs, according to the site between the 15000 and 20000 Euro. Might be interesting if you have a big house. Terraced house for my hope that an air pump as much living as a central heating boiler HRe. If so, then the choice is quickly made. An air heat pump uses electricity only com and consumption costs are lower. My power I involve Green Choice and is green power. That way I can the CO2 footprint of my house even smaller.