This is the 1598th most frequent Russian word.
сэкономить
"To save" (money, resources, etc.).
In this sentence, 'сэкономить' means to save or economize, referring to the act of using less money or resources while achieving the same goal.
Я смог сэкономить деньги, покупая товары на распродаже.
I managed to save money by buying items on sale.
Here, 'сэкономить' is used to indicate saving on a specific expenditure, namely electricity.
Мы решили сэкономить на электричестве, устанавливая энергосберегающие лампочки.
We decided to save on electricity by installing energy-saving bulbs.
In this usage, 'сэкономить' implies saving time, meaning to use time more efficiently or avoid wasting it.