Watch Ken Goodwin's report
More than 70 generators are on their way to Ukraine - with some of them big enough to power a small hospital.
Around 25 tonnes of aid is being sent to the country to try to help people through the cold Ukrainian winter, where the average temperatures are below freezing.
It includes dozens of generators, some of which are big enough to power a small village or hospital.
It is part of an appeal by the charity UK to Ukraine and the humanitarian aid fund Great Britain, which has seen villagers in Wiltshire raise hundreds of thousands of pounds.
Olena Golovtchouk, a Ukrainian lawyer based in the UK, says the generators are essential.
"At the moment they are crucial," she said. "Six million people last week were without electricity, this will make a hell of a difference.
"It will bring them food, it will enable them to keep warm and it will save a number of lives of children and elderly people."
There was also enough room on the lorry for toys and chocolate, with schoolchildren helping to pack them to try to provide a bit of Christmas cheer to the families living through the war.
One of the children said: "I hope they will be very pleased because I think everyone should have a nice Christmas."
Another said: "Right now they’re in danger, and they are probably not as excited as much as they would be for Christmas because they won’t be able to get lots of presents and they won’t be able to celebrate with all their friends and family."
The charity says that the project has been a massive effort from many volunteers.
Caragh Booth, from UK to Ukraine, said: "It’s been a fantastic community effort, absolutely incredible, and we are thrilled to bits to be loading this incredible truck here is extraordinary."
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