Record numbers of consumers switched energy supplier in July despite the summer holiday break, but millions are still paying over the odds for their gas and electricity, according to the Energy Advice Line.
New government figures show that 333,653 customers switched suppliers last month - 22% more than at the same time last year - bringing the total number of switchers for the year to 2.7 million.
"These figures are obviously good news, as switching is the best and cheapest way to save money on your energy bills," Mr Morgan said. "This fact is confirmed by the government and the regulator.
"The problem is that according to a recent report by the Competition and Markets Authority (CMA), 70% of the customers of hte Big Six suppliers are languishing on the most expensive standard tariffs.
"In other words, the vast majority of energy consumers in the UK could switch to a much cheaper deal - and save £300 a year in the process - but they don't.
"So while these recent figures are a step in the right direction, there is still a very long way to go."
The figures also show that 76,174 customers switched to small and medium suppliers in July, representing almost one-quarter of all switches. Mr Morgan said that this suggested consumers continued to lack confidence in the Big Six suppliers.
The government claims the record number of switchers is a result of government initiatives to make the switching process simpler, and by highlighting the benefits of changing supplier.
But Mr Morgan said more incentives were urgently needed to incentivise long-term non-switchers to engage with the market and save money in the process.
"Various initiatives have been put in place, such as providing customers with clearer and simpler information on their bills in order to be able to compare prices more easily," Mr Morgan said.
"But lots more needs to be done to persuade people who never shop around to do so, and to convince them that the savings that can be achieved can be considerable."
"I urge anyone who hasn't switched supplier recently - particularly the large numbers who haven't done so for years, to seek out some of the great deals that are around at the moment," Mr Morgan said.
"Using a reliable and independent service like the Energy Advice Line makes it quick and simple, and could potentially save you hundreds of pounds."
The Energy Advice Line is one of the UK's leading price comparison and switching services for business and domestic energy customers. It is also an advocate for energy market reform and has campaigned for a better deal for energy users, including calling for a ban on cold calling and changes to regulations to make it easier for all consumers to switch suppliers.
The service is completely independent and free. Consumers can quickly and simply search the market for the best available energy deals from an extensive panel of small and large energy suppliers. The service also offers a free advice line for business energy customers.
For further information visit energyadviceline.org.uk