Today the Secretary of State for Energy and Climate Change, Amber Rudd, will give a speech to update us all on the Government’s energy policy. What she will say has been widely trailed and it contains some seriously bad news.

The last six months have seen a relentless and systematic unravelling of the excellent work done by Ed Davey to develop the green economy. The Government is now going one step further to deprioritise decarbonisation as a main goal, in favour of making energy security its number one priority. It does not seem to realise it is possible to deliver on both.

Amber Rudd will say she plans to curb the growth of renewable industries even further, with the logical conclusion that there must be an increase in nuclear and gas to meet energy needs. This means expensive subsidies paid to other countries, rather than investment in renewables in the UK, and also fracking.

The most baffling aspect of the Government’s abandonment of the renewable sector is the fact there is such a strong business case for investing in green industries. We might understand their actions if it was just about environmental concern, which Conservatives have never been strong on, and we know of the power wielded by backbench climate-change deniers and fossil fuel lobbyists. But to ignore the long-term economic case in favour of short-term cash gains is extraordinary. The UK has been a world leader in this sector and continuing to invest and develop these job-creating industries while we have a competitive advantage and while the costs of producing renewable energy are plummeting is simply good economic sense.

The timing of this speech is extremely worrying, being just a fortnight before the most significant global conference on climate change that there has ever been. The UN Climate Conference in Paris is a precious opportunity to build a worldwide consensus on tackling climate change. Undermining the UK’s clout in those discussions could potentially have devastating consequences.

It is clear now, if it wasn’t before, that the good work of the Coalition on green issues was entirely down to work of Liberal Democrats. Left on their own the Conservatives have shown that there is no genuine commitment to tackling climate change at all. Amber Rudd’s accusations that DECC over-spent over recent years are inaccurate and quite simply a smoke-screen for politically motivated cuts. The ending of electricity from coal announced today is of course good news, but what most people don’t know is that the Conservatives repeatedly opposed Lib Dem plans to do this during the Coalition. Cost pressures have finally changed their mind.

But while it angers us all to see what the Government is now doing, we should be careful to remember that their actions can only go so far in unpicking what Lib Dems achieved. The solar panels we put on roofs will remain. The wind farms we opened will continue to contribute towards our energy needs. There may be no new ones thanks to the Tories, but we can still be proud of the positive difference we have made. We must continue to fight for a greener economy because we have shown that our actions match our words, and it is clear that for the Tories they do not. Unfortunately Amber Rudd’s speech today makes that crystal clear.

* Lynne Featherstone was the MP for Hornsey and Wood Green from 2005 to 2015, and served as a minister in both the Home Office and Department for International Development. She blogs at www.lynnefeatherstone.org.