926. Those who do have access to a home chargepoint can reduce costs further by charging overnight. The Review's analysis found that if 50% of people with home charging use an overnight tariff (modelled on the current 'Intelligent Octopus' tariff), they could make annual savings of £250 by 2040 or £600 by 2050 on average. By charging overnight, people will call on the grid when demand is lowest. Those on time-of-use tariffs (where suppliers charge different prices for using energy at different times of the day) can save households money. To enable this for more households, the government should continue with plans to ensure that as many households and businesses as possible benefit from smart metering and should work with the sector to increase the provision of new energy supply propositions in the retail market - including smart time-of-use tariffs. It is important to recognise the potential of smart systems and other household technologies for reducing energy demand. The need for smart, flexible solutions to help balance the power grid is also set out in Pillar 2. Households that also have solar panels installed can bring down costs further, by using energy from them to charge their vehicle. Additionally, 'vehicle-to-grid' technology allows electric vehicles to be used to store energy which can then be sold to the energy grid, which could cut down costs for consumers significantly.647