The inspections are set to begin of the botched Renewable Heat Incentive Scheme boiler sites.
At least 20 sites will be visited in the first phase of the planned inspections with a second phase put out to tender in the Autumn.
The Department of Economy had been left considering its options after the initial tender process to find auditors failed to find a suitable contractor.
As a result a plan for an inspection of all sites was shelved - there are 1,270 businesses with 2,100 boilers in the scheme.
The Department has appointed Ricardo Energy and Environment to undertake the inspection programme.
It will commence next Monday and will consist of both announced and unannounced inspections.
The process will involve a technical check and business analysis of each installation. Inspectors will be looking to see if the heat is being used for an "eligible purpose and whether there is any evidence of heat being wasted".
It will also inspect whether the owners are complying with the Scheme regulations and guidelines and whether the heat use is "economically justifiable" and if the energy management conforms to "industry standards and best practice".
There are a number of enforcement actions which might be taken as a result ranging from providing advice on how to increase energy efficiency, the withholding of payments, financial penalties, or permanently excluding participants from the Scheme as set out in the Scheme regulations.
All non-domestic RHI recipients have received notice this week that their sites will be inspected.
Established in November 2012, the RHI scheme was an attempt to increase consumption of heat from renewable sources. It was found to have paid more to boiler owners than the cost of the fuel. Auditors said there may have been potential fraud in order for some owners to profit from the scheme.
It landed the Executive with an estimated £490m bill over the next 20 years.
The scandal ultimately led to the downfall of the Executive and the current political deadlock. An inquiry has been established in order to examine the detail of the scheme and how it was allowed to get so out of control.