Art. 14 I Directive 2019/944 for the internal market for electricity:

"Member States shall ensure that at least household customers, and microenterprises with an expected yearly consumption of below 100 000 kWh, have access, free of charge, to at least one tool comparing the offers of suppliers, including offers for dynamic electricity price contracts. Customers shall be informed of the availability of such tools in or together with their bills or by other means. The tools shall meet at least the following requirements:

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(h) they shall perform comparisons, while limiting the personal data requested to that strictly necessary for the comparison. Member States shall ensure that at least one tool covers the entire market.

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