12.14.15
COP21 – Turning Good Intentions into Concrete Actions
The countries of the world have agreed to reduce carbon emissions significantly by 2030. Although this agreement is designed to limit the forecast rise in global temperature I am more enthusiastic about the fact that it will result in reduced consumption of non-renewable hydro-carbons.
But now comes the hard part. How to decide which actions will produce the maximum benefits for the least cost and economic disruption.
I’ll start by listing a few things that I don’t think should be priorities.
Roof-top solar panels: there will be a great temptation for governments to jump on the roof-top solar bandwagon. It sounds like such a great idea – let people generate their own power. And many, many countries are doing it so it must surely be a good thing – right?
There is nothing evil about roof-top solar panels. But an objective analysis of all the possible ways that renewable energy can be generated would have to conclude that providing financial support for roof-top solar is one of the most expensive and least effective approaches available.
On the other hand I am an enthusiastic supporter of utility scale solar developments between latitudes 35 north and south such as those built over the past few years by Kauai Island Utility Co-op. Solar energy in the equatorial/subtropical regions is probably the best source of renewable energy available.
The reason I don’t support the development of solar energy north or south of 35 degrees is not because there isn’t solar energy potential at higher latitudes. Obviously there is. The problem is that at higher latitudes the electricity demand usually peaks in the winter and there is significantly less solar energy available in the winter outside the equatorial/subtropical regions. At 35 degrees winter insolation is theoretically about 75% of summer. At 45 degrees the ratio is 66%. But actual generation is much, much less than that because in the winter the low sun angles mean that nearby trees, buildings, and hills place the solar panels in the shade for much of the day. So, for example, in Germany the winter solar generation is 1/10 the summer generation.
Wind: There is no doubt that the extensive development of wind energy is already and will continue to be one of the cornerstones of a sustainable energy environment. The increasing capacity of individual turbines and the decreasing cost/MW make wind energy a very attractive option – when it is available. And that is the big problem with wind.
Although it is true on a global scale that “the wind is always blowing somewhere” it is a fact that calm winds can extend over very large geographic areas for hours or days at a time. It is not uncommon for wind generation to be at less than 10% of nameplate capacity for 30% of the hours in a year. Dealing with the variability of wind will be perhaps the biggest challenge to be overcome in order to meet the carbon emission reduction targets envisioned in the COP21 agreement. Until some progress is made in this regard the financial support provided to wind developers should be significantly reduced.
So much for what should not be priorities.
It is clear that solar and wind can be developed to whatever scale is required and that the cost to do so is not unreasonable. The only remaining problem is how to handle the times when solar and wind are not available. The vast majority of financial support and Research and Development should be directed towards addressing that single issue.
In equatorial and subtropical regions this problem is well defined and can be addressed through energy storage systems that exist today. Solar energy is very predictable and by building enough solar generation to simultaneously meet daytime needs and charge a storage system it is possible to release energy from storage to meet evening and night demand. The Gemasolar plant in Spain is already providing 24×365 electricity generation using only solar energy.
The proposed Kapaia power plant will use solar energy stored in batteries to provide electricity in the late afternoon, evening and through the night. The Noor1 plant in Morocco will have the largest molten salt storage capability in the world when it is completed in 2017.
These positive developments in short duration energy storage should be encouraged by providing the same kinds of financial and regulatory support currently used to encourage wind and solar developments.
Outside the equatorial/subtropical regions the problem is much more difficult.
Wind generation can never truly replace fossil fuel or nuclear generation – it can only displace those traditional sources. By that I mean that regardless of how much wind capacity is developed there will be times when there is simply no wind energy to be harvested. During those times dispatching fossil fuel generation is the only way to keep the lights on.
Energy storage systems will help cover short duration periods of calm winds but they will be unable to solve the problem completely anytime soon.
Roger Andrews and Euan Mearns have done a lot of detailed analyses on large scale energy storage scenarios and have demonstrated quite convincingly that the scale of storage required to truly address calm winds is impractical. I would have to agree.
So if storage can’t solve the wind intermittency problem what approaches might work? I see three possibilities all of which are deserving of investment and regulatory support;
- Development of reliable and renewable energy sources. This would include Geothermal Resources such as the potential 1.6 GW under the Salton Sea and the estimated 25 GW of hydro-kinetic energy available for development in the U.S. alone. These reliable sources of electricity should receive financial support through R&D grants, accelerated capital write-offs and feed-in-tariffs in recognition of their superior value as compared to wind. It would also be possible to implement additional generating capacity at large scale hydro developments that could be used for short durations when winds are calm in a concept I have referred to as unpumped storage.
- Demand response. Post-Fukushima Japan has demonstrated the true power of demand response with peak demand being reduced by as much as 10-15% through the direct action of individuals and businesses. The key ingredient to success is a broad engagement of the population through advertising, public service announcements, and educational programs. It is clear that people will modify their use of energy if they are mobilized when electricity is in short supply.
Another mechanism for reducing peak demand over the long term would be the widespread use of geoexchange technology in preference to traditional HVAC systems. Requiring that geoexchange be integrated into any new commercial and industrial buildings would be a very low cost and effective way to significantly reduce demand.
- Development of a capacity market: I stated before that wind generation displaces fossil-fuel generated electricity. That would not be particularly problematic except that it seriously impacts the profitability of operating those fossil-fuel plants.
In Texas utilities took out a full page ad describing the deterioration in reserve capacity that the increasing penetration of wind energy is causing.
In Germany the development of a “grid balancing market” is helping to deal with fluctuations in wind output but there are problems with this approach.
Although the idea of paying for a duplicate set of generation assets is not appealing it might well be the most effective way to increase the amount of renewable generation that can be developed.
How quickly Can These Measures Be Implemented?
Building code changes to encourage or require the use of geoexchange can be put in place almost immediately. The same is true of changes to the operating practices of Independent System Operators so that organizations storing energy for later use are not charged a grid transit fee.
A feed-in-tariff (FIT) for electricity produced from storage and for reliable renewables such as geothermal and hydro-kinetics would take a bit longer but can certainly be available in less than a year or two. Public education and awareness programs with real-time indications of energy use can be delivered in the same time frame.
Development of a capacity market will require investigation and a thorough analysis of options. But an early commitment to a capacity market would send a positive signal to the operators of the fossil-fuel generating plants that will be needed during the transition to more dependence upon renewable energy sources.
The COP21 agreement represents an historic opportunity to make real progress towards developing a truly sustainable energy environment. But it is quite likely that political leaders will continue to support strategies that are not optimal and could encounter very significant barriers as the amount of renewable generation increases.
To quote Yoda “if you choose the quick and easy path as Vader did – you will become an agent of evil.” That may be a bit dramatic but I think the danger is real. As we move forward with the development of renewables the difficult challenges regarding energy storage need to be addressed as a priority.
@enrgy_manifesto
