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Tag Archives: grid balancing

German energy balancing

By Dave Elliott

Germany is in the lead globally with its ambitious renewable energy programme, already supplying over 32% of its electricity and aiming for 80% by 2050.  At present, Germany’s 1.5 million photovoltaic solar installations have a generation capacity of over 40GW, four times the remaining 10.8 GW base-load nuclear fleet that is being decommissioned in stages between the end of 2017 and 2022. PV can be well matched to day-time peak demand in Germany, which is why it has challenged gas peaking plant in this market.  However, due to its low load factor (10-15%, compared to 70-80% or more for nuclear), solar PV generation only delivers around 940 equivalent full-load hours of electricity per year, so in 2015 its high capacity only met around 7.5% of German electricity demand, compared to 14% for nuclear generation. That’s why some think it is not the best option to expand for the future – it’s expensive for relatively low levels of actual output. (more…)

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EU e-Highway 2050

By Dave Elliott

A recent report says that long distance transmission grids offer many advantages including enhanced cross-EU trade and grid balancing opportunities, enabling high levels of renewables to be used while reducing curtailment of occasional surpluses. The European Network of Transmission System Operators for Electricity group had already addressed the development of the pan-EU electricity transmission network up to 2030 in a Ten-Year Network Development Plan. Starting with that, the e-Highway 2050 research and innovation project has now looked to 2050: it deals with the transition paths for the whole power system, with a focus on the transmission network, to support the European Union in reaching a low carbon economy by 2050.

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Storage will cut renewable balancing cost

By Dave Elliott

Energy storage is all the rage at the moment, with a Daily Telegraph columnist even claiming that ‘cutting-edge research into cheap and clean forms of electricity storage is moving so fast that we may never again need to build 20th Century power plants in this country, let alone a nuclear white elephant such as Hinkley Point’.

And it could be cheap. The recent Carbon Trust/Imperial College report on energy storage says that ‘the UK can realise significant cost savings if market arrangements for the electricity system allow for an efficient deployment and use of energy storage, alongside other flexibility options such as demand response and interconnectors’. It claims that many of the changes needed ‘are likely to be cost neutral and require no additional funding from the government’.

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The end of power utilities? Maybe not just yet…

By Dave Elliott

Local generation is challenging the power utilities in the US and elsewhere. Some of the implications of that trend are reviewed in a useful series of studies by the US Lawrence Berkeley National Labs on Future Electric Utility Regulation which look at Regulation in a High Distributed Energy Resources Future i.e. in the context of a potential future with a high reliance on energy efficiency, peak load management, distributed generation and storage.

One of  Berkeley Lab’s  studies (No.1 in the series) focuses on regulation of Distributed Energy Resources in terms of  advantages and disadvantages from the perspectives of utilities and customers and the potential role (if any) of the big power utilities in the future. The report says that the emergence of distributed energy resources (DERs) that can generate, manage and store energy on the customer side of the electric meter is widely recognized as a transformative force in the power sector’. It suggests that, as DERs become competitive in price and performance for many customers, ‘utilities will face reduced sales volume, more elastic customer demand, and greater opportunities to substitute DER optimization for traditional utility assets and services. It expects that ‘dramatic reductions in the cost of regulated distribution networks will be sought by all stakeholders’, and, although that could be good for all concerned, it raises the question of whether utilities will or should bother trying to enter DER markets, given what might be diminishing returns.

Certainly it says that it is not a straightforward decision, quoting Gregory Aliff, Beyond the math: Preparing for disruption and innovation in the US electric power industry, (Deloitte 2013): ‘A decision to transition to a higher overall risk profile will likely involve significant internal debate and high probability of negative reactions from the financial markets and shareholders. This barrier may ultimately be deemed insurmountable – and as a consequence, new business alternatives may be severely constrained.’

That has evidently already been judged to be the case in Germany, where companies like RWE and E.ON have in effect lost monopoly control of the consumer electricity market as prosumer self-generation  and local energy co-ops have spread, with PV solar especially challenging the utilities’ gas-fired plants in the lucrative peak demand market. The big utilities have had to retreat to servicing this new decentralised market (which accounts for around 40% of Germany’s renewable capacity) and managing the grid. The Berkeley report seems to suggest something similar may happen in the US – but with the added issue of trying to ensure that consumers stay on the grid. There’s evidently concern about ‘grid defection’. That would make managing the system (e.g. balancing variable renewables and variable demand) much harder, potentially undermining the role of DERs and making life hard for the utilities.

Instead, the Berkeley Lab report says that ‘by facilitating DERs, utilities can both lower their costs and increase the benefits they can offer customers who deploy DERs, providing an incentive to remain connected to the distribution system rather than defect from it’.  It adds ‘the fundamental role of the utility will evolve to support this lower cost, higher value service that can be provided when customer-facing DERs are coordinated to not only provide customer services, but to create value for the distribution utility and grid as well. However, that evolution may occur in different directions. One points towards a major utility presence in sourcing, financing and optimizing DERs for customers. The other points towards a major role for competitive firms in not only providing DERs through competitive channels, but also in competing to tailor DERs’ performance and optimize the total value they can create in this emerging, three-sided market comprised of customers, distribution utilities and the grid itself.’

The report also suggests that, in the US context, regulators may in any case not let utilities enter DER markets, quoting a comment in a recent New York Public Service Commission Order: ‘Markets will thrive best where there is both the perception and the reality of a level  playing field, and that is best accomplished by restricting the ability of utilities to participate’. Before the New York Public Service Commission, Order Adopting Regulatory Policy Framework and Implementation Plan, Case 14-M-101, Proceeding on Motion of the Commission in Regard to Reforming the Energy Vision, Feb. 26, 2015, p. 67.

The Berkeley Lab report seeks to steer in between rival views. One says that, having lost their market monopoly, the utilities will fade away, the other that their supply system will always be cheaper than DERs, or if not, that utilities would be best suited to deploying DERs. Instead, the report says that the utilities will not disappear, but they will have to change their role, from monopoly suppliers to energy service companies and new decentral market enablers, with only limited involvement in generation themselves, as opposed to supporting local distributed generation by others.

Maybe so. They do after all have the expertise, even if they may have lost the trust of consumers. And their traditional markets. Though the exact balance between the various possible elements of the new role that utilities might play is unclear, with the report suggesting that in one, utilities successfully evolve to play the major role in using DERs to provide services to customers, while in the other, ‘these functions are increasingly performed by competitive firms using advanced and largely decentralized digital technologies, and the utility “sticks to its knitting” in terms of providing and maintaining infrastructure needed to deliver basic energy and capacity services, while depending on DERs to entice its customers to remain connected to the system and help the utility maintain sustainable cost levels’.

 Either way, though, their role will be very different from now – and that’s a conclusion that has emerged after just an initial wave of successfully grass-roots decentralized power initiatives. Who knows what may come next, with, for example, pressure for municipal-level energy projects beginning to emerge and some US prosumers banding together in local shared ‘community solar’ micro-grid schemes and peer-to-pear trading: www.renewableenergyworld.com/articles/2016/05/municipal-solar-and-microgrids-a-pv-market-outlook.html  and www.smartgridtoday.com/public/Solar-CEO-sees-clout-growing-for-energy-prosumers.cfm. It does seem that we are moving away from centralised monopoly power. Though against some opposition, as this report from the US indicates: https://ecowatch.com/2016/01/29/rooftop-solar-wars/

Battles over net metering, with utilities trying to limit their losses, may lead more consumers to consider going off-grid. A recent Wired article claimed that, with domestic self-generation, smart meters and local storage  ‘the national grid itself may become less important’, in that ‘we could be living in a world where consumers have super-efficient homes and are mainly generating on site’. http://www.wired.co.uk/news/archive/2016-01/25/smart-grids-empower-users  Certainly some say off-grid systems can be viable in some locations: www.academia.edu/25363058/Emerging_Economic_Viability_of_Grid_Defection_in_a_Northern_Climate_Using_Solar_Hybrid_Systems.

That may happen to some degree in some countries and locations but, overall, the reality seems to be that grids, linking to larger geographically-spread generation projects, will remain vital for balancing local variations in supply and demand, although utilities will have to adapt to a new pattern of energy generation and use.

*The Berkeley Lab reports: Report No 1: Corneli/Kihm, Electric Industry Structure and Regulatory Responses in a High Distributed Energy Resources Future.’ Report No 2 in this ongoing series looks at market design and distribution issues, including local peer-to-peer exchanges between projects and consumers.

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Capacity market mess

By Dave Elliott

The UK’s new Capacity Market auction process aims to ensure that there is enough capacity to meet demand by contracting with suppliers to be available when needed. However, it has failed to deliver any new gas projects, as well as failing to back much in the way of demand-side balancing – just 456MW. As with the first round, which gave contracts for 2018-19, it’s ended up mainly just backing old gas, coal and nuclear plants – with £1bn in contracts for 46GW overall for 2019-20. Most only get 1 year contracts, but the 650MW of new small diesel sets have 15 year contracts, and in all £155m. The 220MW of existing diesel get £93m. So much for clean energy!

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Renewable Integration – a view from Germany

By Dave Elliott

High shares of wind and solar power transform the entire power system and can lead to additional system integration and back-up costs aside from building the power plants themselves. A new background paper from Agora Energiewende examines these dynamics and concludes that, not only are the direct integration/balancing costs low, but so are the controversial indirect costs associated with the variable utilization, in balancing mode, of conventional plant – as long as the power system becomes considerably more flexible.

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UK Energy and the EU: integration or isolation

By Dave Elliott

The UK may be island based but, as renewables expand, it will need more grid links to the continent for balancing and trade. It may have a net surplus and so could do very well selling it over supergrid interconnector links to EU countries less well endowed with renewables. The UK’s National Infrastructure Commission (NIC), which seems to be taking a leading role in energy system planning, said in its recent report ‘Smart Power’, that interconnection, along with storage and demand flexibility ‘could save consumers up to £8 billion a year by 2030, help the UK meet its 2050 carbon targets, and secure the UK’s energy supply for generations’.         

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Prosumer integration

By Dave Elliott

The German Environment Agency (UBA) has produced a comprehensive review of options for removing almost all (95%) greenhouse gas emission by 2050, based on the existing 80% renewables programme for electricity supply, but also looking at all the other sectors – including heating and transport. As I said in my coverage in an earlier post, that is pretty challenging. But it says it can be done. www.umweltbundesamt.de/publikationen/germany-2050-a-greenhouse-gas-neutral-country

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Greenpeace 2030 UK energy scenario

By Dave Elliott

85% of UK electric power could be supplied from renewables and low carbon sources by 2030, says a report for Greenpeace, produced by Demand Energy Equality.org. Basically it looks at a Greenpeace high renewables 2030 supply scenario to see if it can meet demand over the year, given demand peaks and weather changes – it uses 11 years of hourly weather data. And crucially it tests whether it is possible to meet a large part of the heat demand from renewable electricity, given that ‘even modest levels of heat electrification result in large increases in peak electrical demand’. It concludes that it is, but that this will only be possible if domestic heat demand is reduced dramatically, by near 60%. That is seen as vital since ‘electrification increases the size of demand peaks on the electricity network; while decarbonisation (via renewables) in turn decreases the predictability of supply intended to meet those (now increased) peaks’. And so ‘if electricity is the medium by which a reliable and clean energy future is to be delivered, then heating demand reduction must be achieved alongside heating electrification’. www.demandenergyequality.org/2030-energy-scenario.html

On the supply side it sees wind energy growing from 13 GW to 77 GW, 55 GW offshore, 22 GW onshore, with PV solar rising from 5 GW to 28 GW. There is also 8 GW of tidal, some biogas use (but no biomass imports), including around 20 GW of local CHP (fired with gas and some biomass), but no new nuclear and no CCS, just around 20 GW of gas CCGT and some demand side management (DSM), to help with balancing. However, interestingly, domestic DSM only ‘plays a modest role in mitigating periods of deficit. Fewer than 7 periods in which total demand shifting exceeds 3 GW occur on average each year’. That is partly because DSM is as yet in its infancy and the report focuses on established technology. But it does report some interesting DSM developments in the industrial sector – where Flexitricity is the first and largest UK provider of national supply-demand balancing services. http://www.flexitricity.com

However it notes the technical, administrative and logistical feasibility of interacting with corporate and large scale power users in this way has not been matched, thus far, in a domestic setting’. That would require National Grid to negotiate contracts to provide demand reduction at peak times with every UK household, and communicate directly with each when needed. Smart meters might allow that, but are still in their trial phase, with many issues to be resolved.

You could say the same of the electric heat pumps that the report seems to see as a key domestic heat supply option; only meeting 25% of the heat demand, not the 90% envisaged in the DECC 2050 High Renewables modeling, but still a lot more than now. Why not also look at green gas for heating (including biogas and Power to Gas conversion) and to the gas grid for supply? It’s already there, with much more capacity than the power grid! While the report does propose some CHP (oddly seen as inflexible) for heat and power, there’s no mention of solar heating and large community-scaled heat stores (as used now in Denmark), and overall it seems overly focused on electricity.

Rather than offering a clever way to balance surpluses from variable renewables, by being able to ramp down power production and ramp up heat production for storage, for use when heat demand was high, CHP is simply seen as producing too much heat in summer. So there is only around 20 GW of CHP included, compared to over 52 GW in the recent Transition Pathways’ Thousand Flowers scenario. And, on the issue of the inevitable occasional electricity surpluses from its large variable renewable capacity, rather than portraying this as a problem, why didn’t it look more to Power to Gas (P2G) to turn it into a solution – making green gas for grid balancing as well as for heating and transport use? It only talks of using P2G hydrogen for vehicles. And why not look to 2-way supergrid links for balancing? As it is, ‘exports only occur once any surpluses have been utilised to the greatest possible extent domestically’, with the level of interconnector exchanges seen as only around 12 TWh p.a. That seems odd, since there is a lot more excess available (apparently near 43 TWh on average) and there may be times when exports of surplus can earn a lot of money, and be more useful/valuable than P2G conversion or other types of storage, helping to balance the cost of importing more when needed at other times. DECC’s 2050 pathway had 30 TWh of imports/exports. It’s a little odd that supergrid links are left to one side, playing a relatively small role in this study, since an earlier Greenpeace report talked them up as a key EU balancing option: http://www.energynautics.com/news/#GP_EU 

Trying to get to 80% renewables by 2030 is pretty demanding. The Pugwash high renewables pathway, on which I worked two years back, only reached around 80% by 2050, pushing it quite hard, with around 100 GW of wind and 35 GW each of PV and tidal: http://britishpugwash.org/pathways-to-2050-three-possible-uk-energy-strategies/ However, that excluded nuclear, long gone by 2050, had 70 TWh p.a of supergrid imports/exports, and only looked to 40% energy savings. By contrast, the new 2030 Greenpeace scenario still retains some left-over nuclear (Sizewell B) and goes for much higher levels of energy saving – and by 2030. That’s a bit of a stretch. It’s akin to the Centre for Alternative Technology’s pioneering Zero Carbon Britain 2030 scenario and adding to the list of challenging and visionary high renewables scenarios: http://zerocarbonbritain.org/ready-for-zero

What it adds in particular is an interesting and helpful test of the operational viability of an ambitious energy mix, although, sadly, it does not provide an economic analysis, arguing that costs are changing too fast to make that useful. While that may be true (and the report does present some examples of falling costs), the absence of full costing may weaken the impact of the analysis – just at the point when the falling cost of renewables ought to be giving them a better chance. Even so, it’s a welcome addition to the pile of studies making the case for renewables, with balancing, as a technically and operationally viable set of options.

* Economic and financial support issues are to the fore in a new global Greenpeace scenario, which I will review shortly. It looks to getting 100% of all energy from renewables by 2050, at no extra net cost, given the fuel cost savings: http://www.greenpeace.org/international/Global/international/publications/climate/2015/Energy-Revolution-2015-Full.pdf

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Could tidal power be big?

By Dave Elliott

IRENA, the International Renewable Energy Agency, puts the technically available global tidal resource at near 1 TW. That is for all types of tidal system, those using vertical tidal ranges (barrages and lagoons) and those based on tidal streams, using the horizontal ebbs and flows (tidal current turbines). In practice, local limitations, access problems and other constraints will limit what may actually be achievable. So how much might be available? (more…)

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