Ключевые слова: banknotes, bill, cash, cheap, cheapness, coins, cost of light, cost of living, costs, dark, ecology, economy, ecosustainability, ecosustainable, electricity, electricity costs, energy, energy classes, energy tariffs, environment, environmental protection, eur, expenses, household budget, increase, increase in costs, increases, light, light bulb, lighting, low consumption, low consumption light bulb, money, ordinary costs, ordinary expenses, saving, savings, sustainability, sustainable, tariff, value,