| Value | Category | 
                                    
                    
                        | 1 | Electricity | 
                                    
                    
                        | 2 | Solar | 
                                    
                    
                        | 3 | Gas Biogas | 
                                    
                    
                        | 4 | Paraffin | 
                                    
                    
                        | 5 | Candles | 
                                    
                    
                        | 6 | Firewood | 
                                    
                    
                        | 7 | Other | 
                                    
                    
                        | 9 | Not stated | 
                            
            Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.