One of the greatest obstacles facing the sustainable energy industry is the lack of large-scale storage. It is widely known that an economical solution to sustainable energy storage is needed in order to adopt the goal of 100 percent usage of renewable energy sources. Many possible solutions to the problem of electrical energy storage are being researched and tested. This article will examine and attempt to determine the viability of some of the most common theoriesabout battery energy storage systems.
Current storage options for electrical energy
Some discussion is required about the current methods and ideas pertaining to the storage of electrical energies. The subject has been the focus of numerous research studies and many theories abound.
The following are the five most common options along with a quick analysis:
Electrical energy
Supercapacitors store energy with activated carbon. They can be nearly instantaneously charged and release stored energy efficiently. Much research is underway to develop more inexpensive and readily available materials. Graphene is one possible material. Large-scale storage is not practical at this time. Supercapacitors hold much promise in the future, but current technology and cost make this a prohibitive strategy anytime in the near-term.
Potential energy
Hydro-electric pumped storage is the most popular type of option right now. Excess electrical energy is used to pump water to an upper reservoir and when needed the water is released to run turbines to generate electricity. This is an excellent intermediate storage system, but on a large-scale basis, the availability and cost of infrastructure is prohibitive.
Mechanical energy
Compressed air and flywheel energy storage hold some promise. This type of system uses excess energy to compress air and the air is then stored until needed. When the air is released, it can power turbines to create electrical power. There are a couple of projects being tested and the results are encouraging. These types of storage are also expensive and require a large infrastructure build-out.
Electrochemical energy
Battery storage also holds promise in the future. The current technology is lead-acid and lithium-ion. Large-scale storage is not feasible with current technologies. Unless a major break-through occurs, battery storage is too cost-prohibitive. There is a lot of research and work being done on battery technology at the present.
Chemical energy
Fuel conversion storage is the most promising option right now. This method relies on chemical reactions to convert electrical energy into an energy form that is storable. One good example of this is hydrogen fuel cells. If this can be accomplished economically, this has the best large-scale and long-term characteristics that are needed for viable energy storage.
This has been a very brief overview of energy storage technology. Currently, no comprehensive solution has been presented for solving our storage conundrum. In a future article, we will explore a very promising fuel conversion process, taking place in Germany. Sustainable energy storage is very important to the viability of a complete renewable energy future. Great minds are at work and confidence is high that a solution will be found.
Solar energy
Storage for solar power requires more than just a set of lead batteries such as what you might find at the automotive store. Rather, you need high-density, high-powered energy storage. Such batteries are the weakest link in the solar energy business. And, batteries require attention in terms of upkeep. If you choose to build a solar panel energy storage battery, you will need to decide between sealed and unsealed batteries. Sealed batteries are safer, but they are less efficient than are unsealed batteries.
You probably know the most common way to store energy, batteries, but there are actually many ways of doing so. One technique is the use of flywheels. Sparing much of the technical detail, electricity is used to power a motor which spins very heavy wheels. Clearly these solutions are rather scientific, so what if there were other ways? Some ideas start by asking the question, 'What will I need this energy for?' and designing a specific solution for that need. Some buildings in New York City, for example, take power at night when electricity is quite cheap and create ice such that during the day, when electricity rates are very high, the building is cooled by blowing air over these very large ice blocks. It is in this way that energy available now may be used later.
Therefore, at night, when your solar array is dormant, you draw power from the grid working against this credit. Solar installers have copious data on average sunlight and can quite accurately size your system such that this day/night issue, as well as seasonal effects will result in the near-elimination of your electricity bill.
Of course, solar power does not have to be grid-tied, but going off grid means additional costs for battery backup, battery maintenance, and the loss of many financial incentives available to grid-tied systems.
