The Guernsey Environment Commission has recommended that the States look into the construction of a submarine electricity cable to France.
It also recommended that the island invest in wind energy and generate more solar energy.
Deputy Lindsay De Sausmarez, chair of the Committee on Environment and Infrastructure (E&I), said consumers are unlikely to see lower bills in the near term.
Carrying out the electricity strategy to 2050 is estimated to cost £1.7 billion.
This is expected to consist of a mix of public and private money.
Ms De Sausmarez said: “I think for the short to medium term we have to brace ourselves for the fact that electricity will probably get more expensive for a while before it goes out in the future.
“Our plan gives us the most resiliency and security of supply with the greatest flexibility and essentially achieves all objectives in the most cost-effective way.”
Currently, 93% of the island’s power comes from a submarine cable that runs from France via Jersey.
Guernsey can only get 60 MW from that cable and if the island needs more, the diesel generators at the power station in the Vale will be used.
The rest of the local supply, according to the United States, is “primarily diesel generation and a modest level of about 350 kW of distributed solar photovoltaics.”
In addition to the new cable, E&I has recommended that Parliament investigate the generation of 65 MW of electricity from wind energy and 10 MW from solar energy.
Ms De Sausmarez said: “If states don’t provide strategic direction or support route D, the default option is for Guernsey Electricity to assume we follow the status quo and the unfortunate thing about that scenario is that it is the most expensive for consumers on the long term.”
The United States has been given six different options to meet Guernsey’s power needs through 2050.
Route A is described as the most expensive at around £1.9 billion and involves maintaining the current cable to France, via Jersey, and upgrading the diesel generators at Guernsey Electricity’s power station.
Pathway B is for more energy independence and involves generating electricity on the island through solar and wind energy.
Route C is described as renewable energy first, retaining the current cable connection to France via Jersey and increasing the amount of local generation from renewable energy sources such as solar and wind.
Path D is E&I’s preferred route, laying a cable directly to France, in addition to exploring wind and solar generation.
Route E must lay the new cable to France, in addition to more solar energy but without wind energy.
Pathway F is to invest in innovative technologies alongside proven commercially viable technologies such as solar and wind to grow the economy through the sale of sustainably generated electricity.
Analysis of John Fernandez BBC Guernsey Political Reporter
Don’t expect your bills to fall any time soon, expect them to rise – that’s the message from the person leading this new strategy.
It’s going to be a tough message to sell during a cost-of-living crisis, something E&I is well aware of, especially with an estimated cost to the Treasury of £1.7 billion through 2050.
At a time when stockholders’ messages are relentlessly focused on fiscal restraint, the difficulty of selling these policies to political peers will demonstrate the added cost of not making a decision.
However, this is a high-level strategic policy, not requiring the states to spend huge sums of money immediately, but instead opening the door to private investment, new jobs and new industries – things that the states as a whole would normally be very happy about .
But there’s no doubt that despite the message that the money doesn’t have to come from the United States, some politicians will automatically be put off by the price tag.
Follow BBC Guernsey Twitter And Facebook. Send your story ideas to email@example.com.