On the issued electricity bills for end consumers and in their promotional materials electricity suppliers are obliged to disclose the shares of individual energy sources used to produce the supplied electricity in the preceding year. These shares must be published in a table, in which the shares of individual production sources are expressed in a percentage and by a pie chart. Consumers must also be provided with information on CO₂ emissions and the radioactive waste resulting from production sources. When a supplier is offering special electricity products, for example "100 percent energy from solar power plants" must to the customers, buying this product, indicate the share in the whole company structure, and in addition, the structure, which refers to the specific electricity product.