Data Centers are helping to deliver emergency power to the power grid with the use of a crowdsourcing business model.

A very specific element of an electrical power grid is that there is no storage. Therefore demand and supply must be the same, in equilibrium, else there is the risk that this power grid shuts down. So in rare situations where the difference between production and demand (= load) is greater than desirable, and when the market for regulating and reserve capacity for power balancing fails there is a ‘power emergency’.

A large number of the high-voltage networks in Europe are linked together. The operators of these networks have agreed to maintain the balance between production and demand (consumption of electricity) in this interconnected grid. On the basis of these agreements the participants have to demonstrate their commitment by holding reserves in order to steer in situations where the grid is not sufficiently balanced.

The emergency power that is needed is obtained in the domestic market for regulating and reserve-capacity. In addition to this TenneT, a European electricity transmission system operator (TSO), also want to use the emergency power capacity of private parties such as Data Centers. Therefore TenneT started the NL Emergency Power Pool Ltd.

NL Emergency Power Pool is a joint venture of companies with an emergency power capacity of more than 500 kW. Its participants receive ample compensation for the occasional provision of generating capacity. The participants retains full access to their own backup provision. NL Emergency Power Pool claims that the one-of costs are earned back in one month and that the variable costs are reimbursed.

The pool contains various companies, particularly data centers but also hospitals, and water companies. Currently the total size is 40 MW and is still growing. TenneT demands for 20 MW capacity at least, with virtually full availability. Something which is usually only achievable with a resource pool.

NL Emergency Power Pool as a pool aggregator is the single point of contact for TenneT. The aggregator organizes everything, including the central control and metering. The control is fully automated. NL Emergency Power Pool will contract with TenneT less power than the sum of the individual capacities of the participants. In this way NL Emergency Power Pool can fulfill its obligations.

The pool helps TenneT in its statutory duty to ensure the reliability of the national power grid to guarantee. With the contracted emergency power TenneT can also support other national grids when they have problems. The company’s goal is an optimal result for the pool participants, within realistic economic preconditions. NL Emergency Power Pool operates independently and is based on a cooperation contract with TenneT.

By creating this pool of emergency power capacity Tennet is using a crowdsourcing business model. The sum of many individual, relatively small, emergency power systems creates a large virtual emergency power system that is serving the needs TenneT. The use of over-contracting makes this virtual resource pool more robust.

The participating Data Centers becoming power prosumers; producing consumers who besides consuming electricity also are creating electricity.

This leads to security and privacy concerns with allowing unrestricted workload migration to and from and within the cloud. Because the requirements of laws and/or internal regulations an organization may decide that it needs to restrict which cloud servers it uses based on their location. Determining the approximate physical location of an object (workload or a cloud computing server) is generally known as geolocation.

To fulfill the security needs of the customer Cloud computing services needs a secure geolocation that can be enforced through management and operational controls that are scalable and can be automated. The ultimate goal is to be able to use trusted geolocation for deploying and migrating cloud workloads between cloud servers within a cloud. The question is how to enforce and monitor geolocation restrictions for cloud servers.

The National Institute of Standards and Technology (NIST) recently published a draft report on this topic: ‘Trusted Geolocation in the Cloud: Proof of Concept Implementation’ . Based on the concept of Trusted Compute Pools the report gives a description of the requirements and the implementation of a proof of concept (a mix of Intel, VMware and RSA technology).

The NIST authors defines Trusted Compute Pools as “physical or logical groupings of computing hardware in a data center that are tagged with specific and varying security policies”, and were “the access and execution of apps and workloads are monitored, controlled, audited, etc.”

The Trusted Compute Pool is based on three principles of operation:

1. Create a part of the cloud to meet the specific and varying security requirements of users.
2. Control access to that cloud so that the right applications get deployed there.
3. Enable audits of that part of the cloud so that users can verify compliance.

With this the cloud computing provider must be able to create and use trusted geolocation for deploying and migrating cloud workloads between cloud servers within a cloud.

If this concept, as proposed by NIST, is successful it would solve a huge cloud computing issue and when used it could make the negotiation and contracting of cloud computing services much easier.

The new delivery model for information processing, Cloud Computing is offering an attractive value proposition:

• Dynamic (on-demand) provisioning of IT resources
• Low cost because of the use of economy of scale and multi-tenancy sharing of resources
• Shorter time to market in deploying resources
• Different cost structure; the shift from CAPEX to OPEX

But although this value proposition is very promising negotiating cloud contacts can be challenging. Especially when the customer want to make the standard contract more suitable for their requirements.

Recently Stanford Technology Law Review has published a paper on negotiating cloud contracts. Partly based on interviews with customers and providers of cloud computing services the article gives an overview of the evolving contract terms for these kind of services. One of the conclusions of the report is that the terms that generated the most negotiation were provider liability, service level agreements, data protection and security, termination rights, unilateral amendments to service features, and intellectual property rights.

With the increasing consumerazation as well as commoditization of IT services and resources, cloud computing fits quite nicely to the needs of individual consumers or small and medium sized enterprises. But the standard contract terms shows some friction with the needs of large enterprises and government organizations and/or special market segments (for example financial institutions). According to the writers of this paper different cloud computing services with different pricing and sets of terms, from consumer-orientated to enterprise-oriented, with specific terms for certain market sectors or functionality are needed to gain new customers.

Based on a forthcoming book about Sourcing (see The Sourcing Initiative) I would like to add some comments on the article.

Wrapped in a number of contractual and legal issues the article, implicitly, touch four basic or fundamental issues when one want to start using cloud computing services from external providers.

First of all there is the very nature of Cloud Computing itself a service offering based on the idea of economy of scale, mass production and commodity services based on commodity resources. Each standard service offering (SaaS, PaaS, IaaS) has a well defined interface. The consequence of this is that the consumer can’t manage or control the underlying components of the service that is provided. The service, by its nature, offers the service as-is. Therefore, customization is by definition not possible. Because with customization you push aside the principals of the underlying business model. Service differentiation by the provider is only possible when the customer base is large enough to maintain the underlying principles of cloud computing. Not every provider or customer understands the principals and consequences of this new business model very well which leads to all kind of difficulties in the negotiation process.

The second issue is the issue of the split incentives also known as the principal-agent problem. As for cloud computing we can translate it to the question if a cloud service provider really act on behalf and in the interest of the customer. This is a well known economical issue that arise under conditions of incomplete and asymmetric information between customer (principal) and provider (agent). Various mechanisms to improve contract design, as described by Paul Milgrom [1], may be used to try to align the interests of the agent.

The third issue is property ownership which can be murky business with non private cloud computing. Property rights has five basic elements (referred to as a bundle of rights):

• The right of possession.
• The right of control.
• The right of exclusion (access rights).
• The right of enjoyment (earn income of it).
• The right of disposition (buying or selling).

The consequence of these different aspects of property is that different parties are able to hold partitions of rights to particular elements of a resource. Therefore when a cloud computing sourcing deal is taking place the partitions of property rights should be grouped into appropriate bundles and assigned so that appropriate economic incentives are created for the owners of each bundle of property rights. If not, there is the risk of discussions about obligations and liabilities.

The fourth issue is lock-in, where the customer organization must make a strategic risk evaluation on the following lock-in categories before engaging in a cloud computing negotiation.

As described by Gregor Petri[2] we can distinguish four types of lock-in:

1. Horizontal lock-in; restricted ability to replace with comparable service/product.
2. Vertical lock-in; solution restricts choice in other levels of the value chain.
3. Inclined lock-in; less then optimal solution is chosen because of one-stop shopping policy.
4. Generational lock-in; solution replacement with next-generation technology is prohibitively expensive and/or technical, contractual impossible.

The  Cloud Computing market is young and still evolving so the overview of legal issues that is given  in the Stanford paper as well as the four issues stated above can help you to gain knowledge to appreciate what is at stake when negotiating  cloud computing contracts.

[1] Milgrom, P., & John Roberts, J., 1992, ‘Economics, Organization and Management’, ISBN 0132246503, Prentice Hall

[2] Petri, G., 2011, ‘Vendor lock-in and cloud computing’, http://www.itsmportal.com/columns/vendor-lock-and-cloud-computing

==============

See also Cloud Computing Contracts and Geolocation

]]> http://infrarati.wordpress.com/2013/01/12/cloud-computing-contracts/feed/ 0 Infrarati clouds http://infrarati.wordpress.com/2013/01/08/tthe-6th-international-datacentre-awards-2013/ http://infrarati.wordpress.com/2013/01/08/tthe-6th-international-datacentre-awards-2013/#comments Tue, 08 Jan 2013 19:10:41 +0000 Infrarati http://infrarati.wordpress.com/?p=1376 ]]> The annual international Datacentre Awards have been announced by the Judges Panel for the 2013 gala ceremony, which takes place in June in London. And as one of the members of the Judges panel I’m looking forward to judging nominations for these awards. The organizers of the event, Broadgroup, have announced an extended panel of expert Judges for the Awards, now in its 6th year. There are 12 award categories and an online entry form is now available at the website datacentreawards.com

Awards 2013 categories:

Category 1: Public Cloud services and Infrastructure

General Description:
Achieving hundreds of thousands of customers globally, many large businesses are deploying public cloud applications. Infrastructure as a service (IaaS) is the most active segment of the public cloud services, but more offerings have been launched, with Platform as a Service (PaaS) advancing rapidly. The Award will recognize a Company, Internal Division or functional team with a demonstrable track record established in the last 12 months that can be used as an exemplar to the global datacentre industry that has achieved transformation of traditional compute.

Category 2: Private Cloud Services and Infrastructure

General Description:
Private Cloud Services are gaining significant credibility offering dedicated services providing IT flexibility and scalability. The capability to host business applications and services is highly dependent upon the infrastructure offering, services wrapper and extent of automation. The judges are looking to identify a business that has an established Private Cloud service. The Award will recognize a Company, Internal Division or functional team with a demonstrable track record established in the last 12 months that can be used as an exemplar to the global datacentre industry that has achieved transformation of traditional compute.

Category 3: Energy Efficiency and Environmental Sustainability

General Description:
The industry is under increasing challenges to ensure energy efficiency and environmental sustainability is at the core of the data centre design and most critically during the lifecycle operation. Data Centre performance is now a crucial measure in the use of the resources spent in the operation of the facility – spanning both new entrants and the existing built environment. The award seeks to identify a business that has significantly demonstrated energy efficiency in the data centre industry. The award will recognize a Data Centre facility, or a team within the owning company with a demonstrable track record established in the last 12 months, that can be used as an exemplar to the European data centre industry of energy efficiency innovation.

Category 4: Co-location Provider of the Year

General Description:
The award is aimed at carrier neutral co-location providers operating shared facilities for multiple customers ranging in size from a single cabinet upwards. You can operate a stand-alone site or multiple locations. The award will be given for the best operator in the marketplace. The judges will be looking at what the extra dimension is that you have brought to the co-location market over and beyond the delivery of the technical aspects of your facility.

Category 5: Datacentre Retrofit of the Year

General Description:
The Judges are seeking to identify an exemplar of best practice in datacentre retrofit over the past 12 months. In providing your case study, the panel will assess technical, environmental, cost, energy efficiency and customer value. If possible please identify the financial scale of the project.

Category 6: New Datacentre of the Year

General Description:
New datacentres are being developed at an increasing rate globally. This award is designed to recognise a new datacentre, either commercial (co-location, hosting, managed services, etc.) or enterprise of any size, which has been deployed in the past 12 months. The award will be given to a datacentre that demonstrates innovation, awareness of its environmental impact, integrated thinking and can show how the facility was developed to meet current and future needs.

Category 7: Managed Services Award

General Description:
The award is aimed at all managed service providers, both large and small. The award will be given for the best operator in the marketplace. In particular the judges will be looking to identify the extra dimension brought by the nominee company to the global managed services marketplace.

Category 8: Operational Excellence of the Year

General Description:
Data centre Operational Excellence is a philosophy of organizational leadership that stresses the application of a variety of principles, work processes, and tools toward the sustainable improvement of data centre key performance metrics (IT and/or Facilities) in combination with lower operating expense. These results may have been achieved by improvements in daily operations and/or maintenance activities.
The judges are looking to identify a business that has significantly demonstrated operational excellence in the datacentre industry. The award will recognize an IT operation team or a Facilities operation team with a demonstrable track record established in the last 12 months, that can be used as an exemplar to the global datacentre industry of operational excellence.

Category 9: Modular Award

General Description:
As performance of devices rapidly increases and the ubiquity of the Internet unfolds, strategies around building the IT infrastructures to support them needs to rapidly evolve too. With a range of modules available, installation is easy with little more than a power connection, a water connection (for cooling) and a data connection. One of the main advantages for modular datacentres the operation of pay as you grow models, as power, cooling and IT scale together. Effectively this delays capital costs but also eliminates unused capacity as the datacentre fills up. With a key objective of achieving the lowest total cost of ownership with time efficiencies, and carbon savings and the opportunity for swift implementation using the latest technologies, modular deployments can offer significant advantages. This Award will be given to the best modular product offering.

Category 10: Entrepreneur of the Year

General Description:
The Award recognises the passion and drive behind entrepreneurial businesses whether private or listed, or private equity backed.

Category 11: CxO of the Year

General Description:
The judges are seeking to identify an inspiring CXO and a true leader example. The person nominated will have a demonstrable track-record of recent industry achievements over the past 12 months, which represent marketing flair, commercial success, significant business growth, uniqueness in approach and industry leadership.

Category 12: Young Talent of the Year

General Description:
This award will recognise a young individual who during the past 12 months deserves singular recognition in regards to their impact on their organisation, their sector and/or the industry. This could include but is not limited to an individual who has demonstrated innovation, significant change, first mover advantage, in term of new services, new business model, or new technology development or deployment. The award is worthy of recognition to someone who has demonstrated courage, tenacity, and creativity in front of established subject matter experts. The judges will be looking for qualitative and quantitative information to support the admission. The young individual will also show significant potential and is likely to be a future leader in the industry. This award may be nominated regardless of affinity or relationship with the person or company.

Category 13: Judges Award

General Description:
This Award is given at the discretion of the Judges Panel. It will recognise an Individual or organisation whose contribution during the past 12 months deserves singular recognition. This could include an industry ‘Ambassador’ or an organisation that has demonstrated first mover advantage; or a contributor: – an award worthy of recognition to someone who has demonstrated tenacity, or a product that has caused a disruptive effect within our industry. This award is frequently the hardest for the Judges to assign. This award may be nominated regardless of affinity or relationship with the person or company.

In the context of a collaboration project between the VU University Amsterdam (Software and Services Research Group) and SURFNet, the VU University Amsterdam developed an on-line library for Green ICT practices. It currently contains 258 practices elicited from both industrial practice and academic publications.

As stated by the project team “In spite of the investments in green ICT, companies and educators lack reusable green practices including operational actions to re-green ICT, metrics, and examples of achieved results. The objective of the project is to make available reusable practices for energy-efficient ICT systems and more sustainable ICT supported processes. By setting up an open green ICT practices library, students, educators and researchers can study and experiment with green practices, and measure the achieved environmental effects and economic benefits.”

Currently the library is presented with a collection of green ICT practices elicited from literature, research/education and industry. It makes explicit their environmental effects and economic benefits, which assists companies and organizations to select the most appropriate green practices for their own green objectives.

The current library can be browsed by category, goal, environmental effect and economic impact.

At this stage they need help to test the library and send them your feedback on usability and any other aspects you deserve as important. Companies that have successful practices and experiences in improving ICT energy efficiency are highly welcome to contribute.

To visit the online library: http://greenpractice.few.vu.nl/.

And for the project description take a look at this site.

Are there with a diminishing PUE still opportunities to improve the energy efficiency of data centers? The answer is yes if you take a different look at energy efficiency.

At the DatacenterDynamics Amsterdam 2012 conference there was a (thought) provoking presentation of Siemens. According to the presenter of Siemens you must take the whole energy supply chain into account. That is starting with the power plant and then following the transmission and distribution grid until you finally reach the IT infrastructure in the data center. The energy efficiency of this energy supply chain is expressed in the Primary Energy Factor (PEF). The PEF is the ratio between the energy delivered at the end of the energy supply chain, the building, and the energy input at the beginning of the energy supply chain. An example. The average PEF in The Netherlands is 2.56. With a primary energy factor of 2.56 it takes 2.56 kWh of primary energy to deliver 1 kWh electrical energy.  So there is a considerable loss of energy in the energy supply chain.

Part of these losses are caused by the energy conversion in the power plant. The other losses, T&D losses, are caused by the Transmission and Distribution grid. In 2009 the average T&D losses for the European Union were 5.9%. The T&D losses for countries with Tier 1 data center markets were for the UK 7.1%, The Netherlands 3.8%, Germany 4.2% and for France 6.1%.

T&D Losses source World Bank and DataMarket

See also this link for T&D losses for other countries

The high-voltage grid in The Netherlands has an exceptional quality and reliability, much better then the medium and low voltage grids. So according to the presenter you could reduce energy losses by connecting the data center ‘directly’ to the high voltage grid and at the same time improve the reliability of the electrical energy supply. By connecting the data center ‘directly’ to the high voltage grid you reduce the number of components that are part of the internal electrical infrastructure of the data center. And by doing so, you improve the reliability of your electrical infrastructure. By making the proper connections you could even dispose the diesel generators that are used for back up.

It was shown that because of the exceptional high reliability of the high-voltage grid you could easily create an electrical infrastructure for a data center with a higher availability then a Tier IV data center as defined by the Uptime Institute.

Interesting and provoking thoughts given the fact what another speaker John Post, managing director of Green IT Amsterdam consortium, was telling. Amsterdam is with London, Frankfurt and Paris one of the four Tier 1 data center markets in Europe. According to him the agglomeration of Amsterdam has currently 36 commercial data centers with a CO2 emission of 720 kiloton CO2/year. That is around 15% of the total CO2 emission in the city. The expectation is that in 2015 it will be 930 kiloton/year or 20% of the total CO2 emission. Amsterdam want to reduce their carbon emission in 2025 with 40% compared with the year 1990. This will definitely have an impact on the data centers. Therefore according to John Post data center providers must seek collaboration with energy providers and think about new business models to solve this issue and at the same time being profitable.

See also the blog entries Following the data center energy track and Power markets, Power prices and Data Centres in Europe

One of the interesting tables that came available is the CO2 emissions per kWh electricity generation. It isn’t easy to find consistent and complete time series. A lot of the data that can be found is using different definitions and/or different time periods what makes it difficult to aggregate these figures. But now time series for the period 1990 – 2010 are available.

I made a selection for the EU countries and added the United States to make some comparisons. As you can see in table 1 (double click to get a better look) there is a steady decrease of CO2/kwH. On average there was a reduction of 37% in the EU. The Baltics with Finland, Estonia, Latvia and Lithuania shows a sharp increase. The same can be said for Sweden but Sweden had already a very low CO2/kwH ratio.

kgCO2/kwH figures for the EU countries and the U.S.

The table also shows a remarkable difference between EU and the United States. In the period 1990 – 2010 the U.S. succeeded to reduce the CO2/kwH with only 10% whereas the EU countries reduced the CO2/kwH in the same period with 37%.

Zooming in on the countries with Tier 1 data center markets United Kingdom, Netherlands, Germany and France (with the DC hubs London, Amsterdam, Frankfurt and Paris) we see a CO2/kwH reduction of 32%, 31.6%, 24.1% and 24.8%.
The Netherlands and Germany follows more or less the trend of the average EU decrease. Whereas the trend of the UK is much bumpier. From 1999 till 2006 the CO2/kwH ratio was even increasing but although the trend is again going down it still didn’t pass the all time low in 1999. And France with its large share in nuclear generated electricity has a more or less steady trend after an initial reduction in the beginning of the nineties.

kgCO2/kwH trends

If we take a look at the United States we see that already in 1993 the average CO2/kwH of the EU countries was lower than that of the US. And 1995 was the year that the CO2/kwH of all the four countries with the European Tier-1 datacenter markets went below the CO2/kwH of the United States.

[Update]

Our friends from Greenqloud were missing a country. Sorry guys no EU member yet  ;)) but  nevertheless  here are the figures of Iceland:

Iceland CO2kwH Data

See also: Power markets, Power prices and Data Centres in Europe

According to SURFnet one of the import features of GreenQloud is that they were willing to make specific changes;  “An important feature is to integrate the authentication framework of the universities (often exposed via SAML, in the Netherlands via SURFfederatie) with the IaaS cloud, in order to do automatic account provisioning”.

Legislation was also a topic that was included in the assessment. According to Dutch law, data needs to stay inside the European Economical Area (EEA). This makes it difficult to use cloud providers that have base outside the EEA, like the US, even though they run in Europe. But Iceland is part of European Economic Area so there are no data legislation issues.

For SURFnet another interesting aspect in using remote IaaS-clouds is the network layer. Research networks are very well connected and via other research networks (inter domain networking) connection can be made to GreenQloud in Iceland via Netherlight, NORDUnet and RHnet. This gives researchers the opportunity to start their machines in Iceland while they’re connected in an institution VLAN and are protected by the institution firewall.

The services of GreenQloud are powered by 100% renewable energy resources. With the transfer of services to GreenQloud,  SURFnet thinks to reduce CO2 emission with 50 ton /year.

GreenQloud, only recently  announced the launch of two clean IaaS cloud solutions, Compute Qloud™ and Storage Qloud™, at DEMO Fall 2012. GreenQloud was founded in 2010 and is privately funded. Verne Global serves as the primary data center facility for GreenQloud, with Thor DC (Advania) serving as an additional location.

See also: Iceland green data center initiatives

Transform Now!

Last week at VMworld Barcelona not only attention was given to products and solutions across the three key layers of Infrastructure, Application Platform and End-user technology but also much attention was given to how to transform the traditional IT department to an IT department that is ready for the Cloud Era.

With a specific conference track, ‘IT Transformation’, VMware paid tribute to the fact that on demand services based on automated and policy based provisioning and deployment will change the current operational model of IT.

With the introduction of cloud computing we are witnessing the transition from an ‘artisan’ way of IT production to an industrial way of IT production. Handcrafted, dedicated IT infrastructure siloes will be converted into industrial made, commoditized and generic, horizontal IT infrastructural platforms. For this, a new operational model of IT is needed to make this transition possible. In several presentations VMware staff told that last year they had worked on an IT Transformation model that must support the customers to make this move.

A 3 steps capability model was presented; starting with a traditional reactive IT organization, according to VMware the IT organization has to change to a proactive service broker and finally should get an position as an innovative strategic partner for the business. To make this happen four worktracks or swimming lanes were defined. The first one is for the well known Technology and Architecture activities to answer the question which technology should be used to build a Software defined infrastructure. The other ones are about answering the question “How do I operate in this new world”. Thus talking and taking action on processes & control and people, culture & organization and IT Business management. VMware anounced that their view on how to transform IT will soon be supported by improved or new products for automated provisioning and deployment and the monitoring of capacities, qualities and costs of IT services. Also new consulting services, education offerings and certifications about IT Transformation can be expected.

VMware made it very clear that the only way you can be succesful in the new Cloud Era is by transforming your current IT organization. Only paying attention to technology is a dead end street. This change will require a lot of effort.

Besides the technology costs the organizational transition costs of cloud computing is something that should not be forgotten.

Data centers, know your power grid

As we all know the quality and availability of the data center stands or falls with the quality and availability of the power supply to the data center. So data centers are very much depending on the quality and capacity of the power grid, for their daily operations as well for their growth potential.

With a scenario of moderate energy efficiency efforts the energy consumption of EU data centers in 2015 is roughly estimated on 105 TWh coming from a 40 TWh in 2006.

At the same time the European Union is transforming its power grid. That is because the European Union defined some ambitious energy targets for 2020 that aims at:

• 20% reduction of energy usage
• 20% share of renewable energy and a
• 20% reduction on greenhouse gas emission

The EU 20-20-20 goals makes it necessary to update the current power grid and to use a larger percentage of renewable energy. On top of this, the EU has an aging power plant fleet. For the carbon based power plants around 60% are in their second half of their life cycle. And in the next ten years decommissioning of 24% of the EU nuclear power, can be expected. (see this blog entry )

Also several ‘incidents’ at nuclear power plants (Japan, France, Belgium) caused a shift in energy policies of several EU countries and has sent shock waves through the energy industry. Germany’s government announced in 2011 that it would phase out all nuclear power plants by 2022. Recently the government in France reaffirmed to cut reliance on nuclear energy from more than 75 percent to 50 percent by shutting 24 reactors by 2025 (see this article).

Until recently experts were expecting that the usage of variable renewable energy sources would require complex control, coordination and power-balancing mechanisms. Instead of a small number of large power plants in the old power grid, the new power grid will link a larger number of small, decentralized power plants with the consumers. In other words power lines will no longer form star-like networks and linking a few large power plants to nearby consumers, but will look more like a meshed network linking many generators with the consumers. There is a fear that such a dense power grid, with intermittent energy sources, would be vulnerable to power outages because it is much harder to synchronize the many generators and machines of consumers.

A good example of this discussion are the recent power grid developments in Germany.

Renewable energy may stabilise the power grid

In contrast of this, scientists at the Max Planck Institute for Dynamics and Self-Organization in Göttingen have now discovered in model simulations that whereas more decentralized grids become more robust to topological failures they simultaneously become more sensitive to dynamical perturbations.

The simulations indicate that decentralized grids are much more robust when single lines are cut (such as the 2006 power outage around Europe, caused by the shutting down of a single line in Northern Germany). A dense grid can compensate more easily, take the extra load, for a line outage.

The transformation of the current power grid raise the question of where to add new connection lines to the already existing grid. The computer model showed that adding new links may not only promote but also destroy synchrony. Adding new lines can hinder power transmission. This counter-intuitive phenomenon is known as Braess’s paradox. It shows that careful consideration should be given to which nodes can be linked without risk.

The expansion of renewable energy still holds challenges for the stability of the grid. The simulation model showed that a highly decentralized grid is more vulnerable to strong fluctuations in consumption. Large power plants can buffer these fluctuations in demand more easily than small ones, The grid can tap into these spinning reserves at short notice to cover supply gaps, an option which is not available in the case of renewable energy sources.

The Network Dynamics Group based in Göttingen currently starts collaborating with network operators to ensure that their findings can be put to practical use. In the meantime, the research group is improving the model. Their current focus is to integrate weather-related fluctuations in renewable energy sources into their simulations.