Czarnecka Marzena:

W: Restrukturyzacja spółek handlowych. Zagadnienia ekonomiczne i prawne, Zeszyty Naukowe AE Katowice „Studia Ekonomiczne" nr 60/2010, s. 19-33

According energy law customer ( doesn't matter consumer Or entrepreneur) can conclude with energy enterprise sale contract and distribution contract or universal agreement

There are mutual agreements, and it means that customer is obliged to pay for services or sale. According art. 6/3a of energy law the energy enterprises may suspend the supply of gaseous fuels, electricity or heat if the customer delays the payment for the gaseous fuel, electricity, heat or the services received for at least a month after the due date of payment in spite of a prior written notification of the intention to terminate the agreement and a designation of an additional two-week long term of settlement of the outstanding and current liabilities. So it means that situation of the energy enterprise is difficult because in practice it haven't any possibilities to demand to fulfil reciprocal performance in the shorter term than this presented in art6/3a of energy law.