More than half of Scotland's electricity demand could be met from green energy, Scottish Renewables has told MSPs.
More wave power could help beat executive targets
The industry forum said independent research showed it could exceed Scottish Executive targets. It took its case to Holyrood on Tuesday.
The executive wants 18% of power generated by renewables such as the wind by the end of the decade.
But Scottish Renewables said it could almost double that figure.
The executive hopes that by 2020, 40% of power will come from green technology but the forum said it could deliver 54%.
The forum told MSPs the right policies need to be in place to meet demand from a wide range of sources, from marine power to biomass - based on wood.
Scottish Renewables, which represents more than 190 green companies and organisations, believes that upgrading the power line from Beauly in the north of Scotland to Denny in Stirlingshire is vital.
The larger pylons would carry energy generated from wind farms and other renewables sources but the plan has been opposed by authorities along the route and is likely to go to a public inquiry.
Chief executive Maf Smith said: "The wrong decision at this critical stage will have devastating consequences for future investment in the industry," he said.
"A veto of the power line, which is designed to link remotely-based generation sites to the national grid, could strangle at birth the new renewables technologies where Scotland currently leads the world.
"This includes marine renewables, both wave and tide power, which has the potential to create up to 7,000 Scots jobs."
He said a recent poll showed 76% of those questioned in Scotland felt it was important that the national grid accommodated new renewable schemes.
The Beauly to Denny power lines plan has provoked opposition
"The fact is that without upgrading the national grid and providing a route for energy produced from renewables in the Highlands and the rest of Scotland, we run the risk of halting investment in Scotland's renewable industry to the noise made by a small but vocal minority," he said.
Mr Smith said other energy providers needed to match the Scottish Renewables achievement in a way that furthered the fight against climate change by reducing CO2 emissions.
He said the words "achievable" and "realistic" should be used to describe renewables targets rather than "ambitious".
Professor Jim McDonald, director of the Institute for Energy and Environment, said: "The electricity industry in Scotland is more than able to show it can plan for a low carbon future, and the onus must surely be on how we tackle our energy utilisation and transport needs over the next 50 years.
"A major challenge for Scotland to realise our potential renewable energy resources is significant investment in the electricity grid infrastructure."
Duncan McLaren, chief executive of Friends of the Earth, said: "Alongside action to improve energy efficiency this study makes it clear that there should be no room for a new nuclear power programme in Scotland.
"If anything, the industry may be underestimating the true potential of renewables as they have taken an overly conservative view of energy saving."
Shiona Baird, the Green Party's energy spokeswoman, said, "The fact that industry has got this far on electricity generation with only half-hearted executive support, really is proof that renewables has massive economic potential."
Richard Lochhead, the SNP's energy spokesman, said: "This report demonstrates once and for all that we don't need expensive dangerous and dirty nuclear power as we have huge potential in wind, particularly offshore wind, wave, tidal, biomass and solar renewables."
Nora Radcliffe, of the Liberal Democrats, said: "Scotland is aiming to be a renewables powerhouse of Europe and the marine energy capital of the world.
"Marine energy in particular offers a win-win-win for Scotland: jobs, exports and emissions reductions."