International efforts to reduce greenhouse gas emissions will drastically impact company valuations -- for better and for worse, depending on the industry.

Companies should start positioning themselves now to take advantage of the low carbon economy, yet executives by and large are unsure of what to expect or how to respond, according to research from McKinsey and Co.

The consulting firm studied six industries -- aluminum, automotive, beer, construction, consumer electronics, and oil and gas -- to try to gauge how climate change mitigation would impact cash flows and valuation.

Cash flows were evaluated based on three scenarios: business-as-usual, the executive scenario, or the greatest degree of change executives can imagine, and the experts' scenario, or the most extreme actions needed to head off catastrophic climate change impacts.

The results varied, but generally speaking, the industries whose cash flows encountered the least amount of stress enjoyed an "underlying structural resilience or experiences fundamental shifts in demand or significantly changed competitive dynamics," McKinsey found.

Sectors that stand to take a hit include oil and gas: if consumption drops as much as is needed to offset the worst effects of climate change, the industry faces long term demand declines beyond 2016. Reduced production and sales could hit upstream companies with a 5 percent drop in valuation under the executive scenario -- and a decline of up to 15 percent in the experts' scenario.

On the other end of the spectrum, the construction industry will likely see an increase in cash flows because of the rising demand for insulation and energy efficiency. Strict regulations could push the value of a representative building-materials company up as much as 80 percent in the experts' scenario, compared to business-as-usual.

Other sectors will see their competitive landscape change dramatically due to emerging technologies and regulatory restrictions. For example, the automotive industry will see their cash flows impacted both negatively and positively as they react to a market that demands fuel efficiency and low carbon energy sources.

"The impact in valuations will depend both on which of these proves dominant and on the ability of the automotive OEMs to pass along the costs of new technologies and part to consumer or to capture value from other segments of the value chain," the report said.

Volatility will also dominate the aluminum industry in which producers must navigate regional regulatory differences and varying access to cheap power.

McKinsey recommends companies position themselves to take advantage of the low carbon economy, including assessing the impact of abatement efforts, building capacities to deal with uncertainty, reviewing investor relations and developing new external links to help them understand and manage climate risks.