There was a lot riding on the flurry of government energy and climate announcements on what was billed as "Green Day" today.

Ministers were obliged to respond to a court ruling last year that the UK's plans to reach net zero were inadequate, to a critical report by its own climate advisers and a review of net zero plans by Conservative MP Chris Skidmore.

It was also under pressure to respond to multi-billion dollar investments in the EU and the US in green technologies, which had prompted businesses to consider moving overseas, and fears the UK would fall behind in the "race to green".

Today ministers published a master 30-page strategy called Powering Up Britain, along with dozens of other documents covering things like electric vehicles and sustainable finance.

But does the strategy really power up Britain, and how much of the cash is new money and simply "rehashed"?

Sky News has broken down some of the headline announcements.

What we already knew: nuclear, risky carbon capture and green hydrogen

A £20bn commitment to invest in controversial technology to capture climate-heating carbon dioxide from the air and store or use it elsewhere had already been announced in this year's spring budget.

Plans for an agency to revive the nuclear industry, named Great British Nuclear, had already been announced more than once. As have plans to accelerate technology for small modular reactors - as far back as 2015.

A pledge of £160m for port infrastructure to help expand offshore wind was announced in 2021, and £240m of funding for green hydrogen projects was announced last year.

The government confirmed it would insulate 300,000 of the worst homes for leaking heat, which amounted to greater detail on a pledge from last year, which will come out of an existing £1bn pot of money.

Kate Norgrove, WWF's executive director of advocacy & campaigns, said: "While there is some wheat among the chaff, today's announcements are a half-baked rehash of existing commitments that fail to meet the strong public call for environmental action."

The new: home heating, electric vehicles and exports

Accelerating electric vehicles

Today the government confirmed over £350m of investment for electric vehicle (EV) charging infrastructure - with charging accessibility being a complaint of many electric vehicle owners. Sky News has asked the government whether this is new money but has not yet received a response.

But what is expected to really drive the switch from petrol and diesel to electric cars is the "zero emission vehicle mandate", requiring a minimum percentage of manufacturers' new car and van sales to be zero emission from 2024.

A new consultation document today sets out minimum sales targets. These would be 22% in 2024, increasing to 80% in 2030 and 100% in 2035.

EV sales already reached 15% of new car sales in the year to June 2022, and the targets broadly track projected sales anyway, according to analysts. Some say the targets should be more ambitious in order to accelerate growth of the second-hand EV market, enabling more drivers to switch to electric.

Funding green

The new Green Finance Strategy - developed by the Treasury, the new Department for Energy Security and Net Zero, and the environment department - sets out how the UK government intends to ensure green finance markets protect and boost the economy and deliver climate goals.

Helping green industries to increase exports

The government has also increased the maximum exposure limit for UK Export Finance from £50bn to £60bn, creating extra capacity to boost exports, including from the UK's clean growth sectors.

Tackling energy use in industry

The government announced an extra £185m for cutting energy use in industry.

The Confederation of British Industry said the various measures today represented a "gear shift to boost energy security, reduce household bills and re-establish the UK's credentials as a leader in green technologies".

What's less clear...

More fire-power for heat pumps

To meet an existing target to free Britain's heating system of gas, all homes will eventually have to get rid of their gas boilers. Many homes will install heat pumps instead, but uptake so far has been slow due to a lack of awareness and supply.

Today the government pledged £30m to help boost manufacturing and supply of heat pumps in the UK - it has not yet confirmed if this is new or whether it comes out of a previously announced £1bn fund.

And it is to consult on a heat pump sales mandate from 2024.

It also extended an existing £5,000 grant to anyone buying a heat pump to 2028, under the Boiler Upgrade Scheme.

However, the government did commit to rebalancing the "current distortions in electricity and gas prices" to ensure electricity is cheaper.

The rebalance will "help reduce the operating costs of heat pumps, electric vehicles and other low carbon technologies," said Sir John Armitt, chair of the National Infrastructure Commission. "The sooner this can be achieved, the better."

What's missing: insulation, North Sea oil and gas

The fact the government didn't aim higher on the millions of homes that need insulating amounts to an announcement of "all padding and no substance", said Cara Jenkinson, cities manager at climate solutions charity Ashden.

The government steered clear of lifting a de facto ban on onshore wind, which could provide cheap power and is relatively quick to build, but is currently bogged down by onerous planning conditions.

"The government still has not understood the priorities and urgency here," said Prof Richard Cochrane, associate professor in renewable energy at Exeter University. "Onshore wind is the cheapest and quickest option" to boost domestic energy security, he said.

The government has so far made little mention of its ongoing licensing of new oil and gas fields in the North Sea, which experts say is at odds with climate targets. Rumours that the Rosebank oil field would be approved have not (yet) materialised.

Nick Molho, who runs the Aldersgate Group of businesses and civil society groups, said "significant gaps" remained. "Further policy detail in areas like home energy efficiency and heating, heavy industry and surface transport is urgently required to meet the challenge presented by increased global competition from the US and the EU, and attract the scale of private investment needed in the UK's low carbon infrastructure.

"Plugging these outstanding policy gaps must be accompanied by the creation of a Net Zero Delivery Body as recommended by the Skidmore review."