Some utilities have maximum demand and/or service charges (Fiji, PNG and Vanuatu) to ensure that larger users pay the appropriate proportion of the use of the grid and total cost of supply. Others (Fiji, Nauru, PNG, Samoa, Tuvalu and Vanuatu) have lifeline tariffs, which lowers the cost for a specified usage amount to assist with affordability of what is an essential service for low-income households. All the other Commonwealth Pacific small states have renewable electricity generation rates of less than 5 per cent.