But outside the talks, investors are voting with their dollars as money flees fossil fuels and migrates to clean energy.
The policy shift at one of the world's biggest and most powerful investment banks is a sign of the times.
This week, Wall Street behemoth Goldman Sachs announced it had ruled out direct finance for new or expanding thermal coal mines and coal-fired power plant projects worldwide, as well as direct finance for new Arctic oil exploration and production.
The bank has also committed to phase out financing for significant thermal coal mining companies that do not have a diversification strategy.
It acknowledged that its policy "still lags behind its leading global competitors" and "remains far from alignment with what is needed to limit climate change to 1.5 degrees Celsius".
So significant is the shift in global financial markets, some believe the world is at a watershed moment.
"The world could well look back on 2019 as the tipping point," argues a new report released today by the Institute for Energy Economics and Financial Analysis (IEEFA).
"[The moment] when global capital markets accepted the technology-driven inevitability [of a] crossover from polluting thermal coal and increased uptake of sustainable clean renewable energy."
Full disclosure: IEEFA is avowedly pro-renewables.
The report's author, Tim Buckley, is also a former head of equities at Citigroup and senior executive at Macquarie Bank, with more than 30 years' experience in financial markets — and the numbers he has compiled tell a compelling story.
Coal shares burnt as renewables shine
Across the globe, the value of clean energy companies is soaring, while the stock of businesses that make their money from fossil fuel energy is in sharp decline.
The picture in Australia is stark.
Major listed coal companies have all "destroyed significant shareholder value over the year", the report notes, with Whitehaven Coal's shares down 37 per cent, Yancoal Australia down 18 per cent and New Hope Corp down 37 per cent.
This at a time when the wider Australian market posted a 20 per cent rise.
In the US, the situation for fossil fuel energy players is even more dire.
Peabody Energy — heavily exposed to both thermal coal used in power stations and coking coal markets hit by a slowing world economy — suffered a 70 per cent plummet in its share price, while Chesapeake Energy, an oil and gas company involved in fracking, was down 66 per cent, according to the report.
Contrast that to the massive gains for renewable energy companies.
In North America, share prices have soared for NextEra Energy, up 38 per cent, and Brookfield Renewable Partners, up 79 per cent, the report found.
In the European Union, over five years, the share prices of renewable energy leaders are up even more: EDPR by 90 per cent, Orsted a whopping 217 per cent and ENEL, 86 per cent.
Climate leadership shifting from government to business
Tim Buckley acknowledges that coal use in power generation will continue for a couple of decades, with China, India and other countries in emerging markets still commissioning new plants today.
But his report argues financial markets, which work by assessing risk and probability, are already looking to a future beyond coal-fired power.
"As the capital flow moves to predominantly bank-rolling renewable energy, the capital market de-rates the incumbent industry players owning now-stranded thermal power plants," he warns.
"The power of financial markets [is] to look ahead to the end game even as technology disruption of energy markets is only now becoming probable.
"It will take decades to play out, but the equity market isn't waiting around."
Other seasoned observers see similar trends.
John Connor — who has been called a 25-year "grizzled veteran" of climate policy — heads the Carbon Market Institute, an industry body for businesses working on a transition to net zero emissions.
He argues that leadership of the climate change response has shifted from government to business.
At the Madrid talks, which he attended, Mr Connor observed the real action was in the business forums on the sidelines.
"It is fascinating looking at the action on the ground," he wrote in an email from the talks, with "more international business alliances being formed than ever before" and "exponential growth" in the number of companies committing to cut their carbon emissions below zero in net terms, by more than offsetting the greenhouse gases they produce.
"We're seeing investors taking action; corporate commitments from companies and countries representing approximately 50 per cent of the market capitalisation of all the stock exchanges in the world (including net-zero by 2050 pledges from the CEOs of 87 of the world's largest companies)."
Report suggests a $13b benefit from renewables switch
In the political debate, there is still a focus on the cost of the transition.
Recall the deep criticism the Opposition received at the last federal election campaign because it could not provide a costing for its policy to cut the nation's CO2 emissions by 45 per cent from year 2000 levels by 2030.
But in the investment world, at least outside of the coal industry, there is a growing emphasis on the potential opportunities and gains from embracing the energy transition.
A report released this week put a value on it for Australia: a $13-billion boost to GDP, in today's dollars, over the next 20 years from moving to a power mix dominated by renewable energy with a more connected national electricity grid, according to the consulting firms PwC and Jacobs.
Australia could have an "energy system that is supplied by 90 per cent renewable power domestically and potentially develop a renewable export market, enabling Australia to become an international player in the export of power," they found.
Government policy might influence the pace of change, but investors and businesses are already deciding its direction.
"The momentum is now unstoppable," John Connor argues, "so it really is now a question of timing, and whether we can move fast enough to mitigate the worst of the climate impacts that are to come."
