TfL eyes renewables contracts to power London's Tube network

[Mark]

TfL eyes renewables contracts to power London's Tube network:
https://www.businessgreen.com/news/4017 ... be-network

City Hall unveils plans to scope out market for Power Purchase Agreements to meet Underground's electricity demand. London's entire Tube network could be powered by renewable electricity directly purchased from wind and solar farms within the next decade, under plans unveiled today by the city's Mayor Sadiq Khan. Transport for London (TfL) is one of the UK's largest consumers of electricity, with its 1.6TWh annual power demand equivalent to that used by more than 437,000 average homes or roughly 12 per cent of all households in the capital. But City Hall said the publication to market today of TfL's renewable electricity requirements marked a significant step towards its ambition to operate a zero emission underground train system in the UK capital by 2030.

The move is aimed at testing the market for securing TfL's electricity through Power Purchase Agreements (PPAs) with renewables generators, which it said would allow Tube trains to be supplied with power directly from wind and solar projects, rather than from the mix of clean and fossil fuel generators offered via the National Grid. At present TfL sources its electricity directly from National Grid via the Crown Commercial Service, but it is aiming to secure deals from the growing PPA market to eventually meet all the Tube network's electricity with renewables. Taking a phased approach, TfL said its ambition was to consider purchasing up to 10 per cent of the network's power demand via renewable PPAs by spring 2022 - subject to market approval from its Finance Committee later this year - with a view to contracting 100 per cent by the end of the decade. "As one of the single biggest purchasers of energy in London, it is important that TfL leads the way on green energy," said the Mayor of London, Sadiq Khan. "This is a vital step towards my ambitions for TfL - and London - to be zero-carbon by 2030."

Continues....

[vtsnowedin]

Would that mean that on a calm dark winter night no trains would move?

[adam2]

No, it is an accounting exercise whereby the electricity supplier to London Transport agree to purchase an amount of green energy equal to the amount of electricity that they sell to London Transport.

I am somewhat doubtful about the usefulness of such schemes. A significant amount of UK electricity is now from renewables, which is good news for both environmental reasons, and energy security.

I am not convinced that any further environmental advantage accrues from an accounting exercise as to what "colour" electricity is sold to which customer.

An illustrative example might be water supply.
Consider a large water tank that is filled partially with raw river water and partially with treated mains water.
Would you drink the water from this tank ? Even if an accountant tells you that the good treated water is supplied to the drinking water tap and the bad river water is used only to water the garden ?

[vtsnowedin]

Mark wrote:

Tube network could be powered by renewable electricity directly purchased from wind and solar farms within the next decade, under plans unveiled today by the city's Mayor Sadiq Khan.

Directly purchased does not sound like an accounting scheme hence my question.
Perhaps the Mayor being a better politician then a scientist fails to understand the difficulties in a direct purchase.

[kenneal - lagger]

I think that it works slightly differently to how you described things, Adam. The green suppliers contracts to sell eleectricity to TfL and uses as much green electricity as they can supply. If they can't supply the full amount they buy in from non green suppliers at a higher price than their own electricity costs. This gives the green supplier an incentive to commission new renewable supplies to enable them to fulfil the contract from their own resources.

So buying from a green supplier encourages the building of new renewable capacity.