Apenheul Primate Park in the Netherlands has calculated annual CO2 emissions from internal activities (e.g. heating, lighting, food preparation) and emissions caused by the fossil-fuel cars the visitors use to and from the Park. Cars caused c. 77% of all emissions and some practical way of offsetting this CO2 load was sought. At Samboja Lestari in Indonesia, research has shown that Sugar palm Borassus flabellifer plantations can be planted and harvested successfully on land previously overrun with Alang-alang Imperata cylindrica grass, which renders the land unsuitable for other forms of cultivation or grazing. The only harvest from Sugar palms is sugar sap and, because sugar is produced from CO2 and H2O, this contains no minerals, phosphate or nitrogen. The sugar can be used for human consumption or, after undergoing a fermentation process, for bio-ethanol, which can then be used as a renewable source of energy. It is predicted that by 2015, Apenheul will be able to offset a substantial proportion of its carbon load from 50 ha of Sugar palms in which it has invested.