Islanders have until March 2024 to get the maximum subsidy from the government to go towards Home Energy Audits.
The surveys typically cost upwards of £400.
1,095 islanders have taken the grants, which takes cuts the price by around half.
Currently, homeowners apply for a maximum of £250 towards the assessment.
Not only does the audit tell people where their houses could be more efficient, but it also explains what islanders can do to lower energy use.
This means households will see cheaper bills along with helping to emit less carbon.
However, the government is decreasing the grant by £100 in the spring.
Jersey's Environment Department wants more people to be able to access the services, so decreasing the subsidy will help more people buy a Home Energy Audit.
The government is focusing on energy efficiency assessments as households and vehicles emit the most carbon dioxide in the island.
Deputy Hilary Jeune, Climate Change Minister, says the government is committed to ensuring hundreds more islanders get their Energy Performance Certificates.
"Lowering the subsidy gradually will help ensure we can support as many people as possible ahead of the upcoming legislation but without taking such a big slice of the climate emergency funding."
The government wants to make the certificates compulsory for every household by 2026.
There will be a public consultation in the new year to see what islanders think about the idea.

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