Category: Renewable

Environmentally-friendly ideas

Here at Synergy Module, we are always looking for good ideas to help the environment. And one good idea that’s come across my desk recently is the building of a DIY home solar panel system by Greg Seaman in the US, who has set one up on his off-the-Grid home. Greg has found that his small system can power all his internet needs (with a router and aerial for wireless broadband), a electric refrigerator (the size of a chest freezer!), a sound system which he can also use to charge mobile devices, battery-powered power tools, and the system even has enough left in it to run a laptop all day. Obviously the great thing about this project is that all of these electrical devices are essentially powered by free energy that did not require any burning of fossil fuels nor release of greenhouse gases into the already over-burdened atmosphere. But other appealing things about the project is that the whole system was built for less than US $1000 or UK £750, is maintenance-free (so far for several years), and the whole system is tucked neatly away out of sight so that it’s not even a blight on the beautiful surrounding countryside.
So what do you need to build one for yourself? Well, I’ll leave the detailed explanations of the actual build to Greg at eartheasy.com, but to give you a quick starter, the main components needed to build a similar system are listed below:

  • Solar panel
  • Charge controller
  • Battery bank
  • Inverter

Of course, you are going to need an array of tools and accessories as well to actually build and fit the system. Some of these tools & accessories you might already have but if not, you will almost certainly have to acquire them. For tools you don’t already have, if you are like me, then you are going to need to do a little research on the right ones to get (which is easily done these days with all the information freely available on the internet). If you are the DIY-type of person, then you know that you are going to make use of building tools in countless other ways over your life time (and that of your kids probably), so it often worth buying the best up front (in my opinion). In any case, below is a list of recommended tools that you should have if you are going to attempt Greg’s home DIY solar panel build:
– power drill and power screwdriver (or drill-driver): probably the most important tool that you will need as you will need to drill lots of holes and use a plethora of screws for the project – read up on local power drill-drivers here.
– power jigsaw: great for all general purpose sawing of several diifferent materials – read some local jigsaw reviews here.
– wiring: needed for wiring between every component in the solar panel system as well as connecting electrical equipment either permanently (like Greg’s fridge) or via wired in power sockets – best value place for wiring in the UK is Toolstation.
– wire cutters and wire strippers: you will be working almost exclusively with electrical wire – for information of which one is the best see here.

SuperGrids

Deeper penetration of renewables onto the electical grid is facilitated by linking regional grids using high voltage interconnects. I am a supported of TREC as you will see from previous posts. I found the following proposal on www.airtricity.com

 

These interconnects act both as a way of landing electrical energy from offshore wind farms as well as interconnecting the grids on both sides of the link. Full details are available on:-

SuperGrid

DR is the enabling technology…

I have huge respect for Dr. Eddie O Connor but I think he is missing the need for Demand Response. DR is a vital requirement for deep renewable penetration as well as large super grids. I just listened to his address at ASPO-Ireland. He explained that if a wind based grid was large enough then production would be level. Even if this is true, demand is not flat.

I understand that Ireland wants to have 33% renewables by 2025. Since wind farms yield 30% of rated output this means that we will have 110% installed plant versus our average consumption. Given that currently the consumption variation from minimum to maximum is nearly 200% this means that at certain times we will be generating, from wind alone, 146% of our demand. Clearly that will result in large periods of wind farm curtailment.

 As far as I know curtailment was planned to start from this summer for wind farms and we are only on 9% renewables at the moment.

If we are indeed peaking on fossil fuels then 33% renewables is not a destination. It is part of the journey. We need to get to a market of renewables plus nuclear eventually. Even if we have large interconnects from Africa to Iceland we need huge amounts of DR to make this possible.

The electrical grid system has evolved over the last 100 years as a flexible supply designed to meet inflexible but fairly predictable demand. Complicated trading systems have evolved to meet the needs of this flexible supply / inflexible demand market. DR is seen as an ‘ancillary service’. It allows for margins of error or enables peak shaving. However most users continue to use electricity on a single tariff and care little about DR. What if the grid, as we know it, didn’t exist? What if it was being developed from scratch now and the only sources of power were solar, wind, hydro, tidal and wave? This would be described as inflexible supply and demand would have to respond to the variability in supply. In order for this grid to be stable there would have to be huge demand response capability built in. You cannot have inflexible supply and inflexible demand.

To my way of thinking the solution is to have realtime pricing on electricity. It may be necessary to let the price of electricity go near zero or even negative at some times to stimulate new markets such as resistive heating and H2 production. Resistive heating as a way of replacing fossil fuel consuption is far better from a carbon perspective than curtailing the wind farms. An obvious market would be municipal swimming pools and public buildings.

Variable pricing will create new markets for low cost electricity and will create both new generation at high cost times (ie CHP or embedded diesel generation) as well as devices that can load shift (ie HVAC and refrigeration).

It is therefore my thesis that DR based on real time pricing is the enabling technology required to move us to a renewables future.

Trans-Mediterranean Renewable Energy Cooperation (TREC)

One of the problems with renewable energy is the inflexibility of supply. This inflexibility is the very feature that requires EDM which is the topic of this blog. EDM can only go so far in balancing the supply and demand of electricity. Another technique is to builld supergrids that link broad geographical areas so that meteorological variations can be averaged.

In 2003 the Trans-Mediterranean Renewable Energy Cooperation (TREC) was founded by the Club of Rome, the Hamburg Climate Protection Foundation and the National Energy Research Center of Jordan (NERC). TREC in cooperation with the German Aerospace Center (DLR) developed the DESERTEC Concept of linking African, Middle East, and Northern European states electrical grids into one supergrid using high voltage direct current (HVDC) interconnects.

This is a fantastic idea. I recommend you visit http://www.desertec.org to learn more and to register your approval for the project in their ‘Give TREC Your Voice’ campaign.

Energy Storage

This blog is about how EDM can help the penetration of renewable energy sources into the electricity grid in Ireland. Another facilitator of renewable energy penetration is energy storage. For example, currently, there is significant interest in pumped hydro storage in Ireland. I have added the URL of the Electricity Storage Association http://electricitystorage.org/ to the blogroll of this site. This URL lists the many options for electricity storage and draws comparisons between them.

It would seem from the analysis that compressed air energy storage (CAES) is an option that might also deserve investigation in the Irish context. This technology uses underground mines or natural caverns to store large volumes of compressed air. During times of surplus electrical energy, air is pumped into the cavern. When electricity is required, the compressed air is used to improve the efficiency of a gas fired turbine.

Off the south coast of Cork in Ireland is the Kinsale gas field which is operated by Marathon. For full details read the following PDF.

http://www.cer.ie/cer04108.pdf

The Kinsale field is now nearly spent and is being used as a natural gas storage facility. The Seven Heads gas field which extends further into the Atlantic uses the pipline and infrastructure of the Kinsale field to land the gas on shore. I began to wonder could the Kinsale gas field infrastructure be used to implement a CAES system. I decided to send the following email to Marathon’s press officers.

_________________________________________

Dear Linda, Robert,

I would appreciate it if you could supply an answer to a technical question, please.

Question Background:  Ireland has a major problem with wind energy penetration due to the variable supply nature of wind generated electricity. Energy demand management (EDM) or energy storage, preferably both, are required to solve the problem. As I understand it, Ireland has 2GW of planning permissions for wind turbines for which grid connections are not possible for reasons of grid instability. I am interested in EDM and energy storage. While researching the technologies behind energy storage I grew a particular interest in the viability of compressed air energy storage (CAES). This form of energy storage is used in conjunction with natural gas to increase turbine efficiency. What is required is a large sealed natural cavern that can be used to store compressed air.

Question: I understand that the Marathon south west gas field, in Ireland, is now being used for gas storage. Could it be used for compressed air storage to help solve Ireland’s wind energy penetration problem?

I would appreciate your feedback on this issue. Please let me know if I can reprint your reply on my blog www.synergymodule.com.

Kindest Regards

Jerry

____________________________________

I look forward to publishing their reply.

19th August 2007

I havn’t heard back from Marathon. I’ll try more local contacts and I will publish whatever reply I get. I think that natural gas wells may not be suitable for CAES because mixing air and natural gas makes an explosive mixture.

In the meantime I found the following two references to the two oldest CAES projects in existance.

Huntorf, Germany

McIntosh, USA

Google and Vehicle To Grid (V2G)

The work that Google are doing on solar energy and hybrid cars is fascinating. Reading the following blog from Google though adds a new element to the mix.

http://googleblog.blogspot.com/2007/06/clean-energy-update.html

Google are growing a fleet of plug in hybrid cars. These are standard hybrid cars with larger batteries fitted and the ability to charge from the electricity grid. The blog also mentions vehicle to grid (V2G) technology. This allows the bidirectional transfer of electricity between the electricity grid and the plug in hybrid.

In the context of Ireland’s need to consume surplus wind generated electricity, electric vehicle or hybrid vehicle batteries would be an ideal candidate for energy storage where the stored energy replaced fossil fuels when consumed on the following day. According to the Irish Examiner (19 June 2007), Toyota are selling 400 Prius hybrid cars per annum in Ireland. Obviously the installed base would have to be much higher to have a significant impact on grid stability.

Wind Power Economics

Last Friday, 8th June 2007, Eirgrid published a paper on Wind Powered Generation which was subtitled ‘An analytical framework to assess generation cost implications’.

http://www.eirgrid.com/EirgridPortal/uploads/Announcements/Windreportv.16.pdf

The report is a very competent analysis establishing the relative cost of electricity generated by wind energy versus by natural gas. The wild-card variable in this analysis is, of course, the variability in price of natural gas from now to 2025 the period of analysis in the report. I was very confused by the predictions for natural gas prices and so I sent EirGrid a question regarding same. The question and their answer are shown below. It’s very interesting that natural gas prices more than doubled and then halved again in one year. No wonder I was confused.

Question

I am studying the energy market in Ireland to identify business opportunities. I need your help understanding one issue. I just read your report about the relative cost effectiveness of wind energy.The report comes out very neutral on the topic. Wind is OK in small doses but we can’t have too much because it destabilises the network. Fair enough! But the whole case of the document was comparing wind to natural gas. The authors had to estimate what the price of natural gas is going to be from now until 2025 to do the sums. They had three scenarios, best, worst and most likely. A consultancy group, Popry, was quoted as a reference for these price estimates.By my interpretation of the natural gas price prediction graph in your report:-

  • Best scenario: gas will halve in price from now to 2010 and then hold that price until 2025
  • Likely scenario: gas will come down by 30% between now and 2025
  • Worst case: gas will go up by 25% to 2025.

Either I am reading this incorrectly, or the whole peak oil thing is not on Eirgrid’s radar. If you put a 5% increase on gas prices per annum, which I would have thought reasonable) then surely the economics swings hugely in favour of wind energy. Are you really basing your predictions on the worst case expectation that energy prices will increase less than general inflation over the next 18 years? The likely and best case scenarios seem bizarre to me.

I’m totally confused. Can you help? Please explain how I am misinterpreting your report.

Answer

Thank you for your question on our Wind Powered generation paper. We would point out that it is a contribution to the discussion on the issue of the economics of wind generation and has been discussed with industry stakeholders and that we do welcome comment.

The price forecasts are based on a period when there was a gas supply shortage in the UK. This had driven prices to historically high levels of 80 cent/therm. The forecast was that these prices would fall back again once additional gas pipeline capacity from Europe to the UK was commissioned in early 2007. So far the predictions have been correct with gas prices now down to 30 cent/therm or less (on the UK gas balancing market).  The low gas price scenario continues on at this low level based on the UK ‘s ability to tap into the global gas market through the construction of large scale LNG terminals.  In the long term if gas prices went to the higher levels quoted, you may see some switching to clean coal technology for electricity generation.

The paper identifies the break even price of gas to be above 80 cent. The reader can then take a own view on the probability of average gas prices over a year being in excess of 80 cent. In the long term as fossil fuels get scarce, it is fair to say that prices could be expected to rise, the unknown is by how much and when.