Negawatt power
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Negawatt power is a term coined for an arbitrage way of supplying additional electrical energy to consumers without increased generation capacity by the creation of a market for trading of increased efficiency. The concept was introduced by Amory Lovins in a 1989 speech.
The concept works by utilising consumption efficiency to increase available market supply rather than by increasing plant generation capacity.
Whilst it is related to and utilises consumption efficiencies, it differs in scale and market behaviour from individual company or consumer level efficiencies.
For example an industrial consumer can advertise for tenders to supply it with say 100 MW hours. A tenderer may find energy efficiencies within an unrelated business and contract to improve their heating or lighting for instance and then sell the saving through the utility to the industrial consumer so it becomes an arbitrage transaction rather than an in house process or requiring increased generation capacity from the electric power utility.
Energy consumers may also reduce energy consumption for a few hours to "generate" negawatts - hypothetical tradeable units of saved energy. By shutting off air conditioners energy can be saved over a short period of time. This reduction in consumption is referred to as a negawatt and can be sold in certain specialized markets (demand response) in the United States.
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[edit] Potential
This "virtual generation" method can supply growth of supply by increasing efficiencies rather than increasing generation.
[edit] Implementation difficulties
[edit] Market
Establishing a market for the trade of Negawatts may require enabling legislation and cooperatation between primary producers, distributors, traders and consumers when these parties have conflicting interests. For instance generators income is commonly derived from selling electricity and their cash flow may be reduced by trade in efficiencies, however increasing supply by raising consumption efficiency is less expensive generally than building extra generating capacity. New markets have developed in several regions across the United States to allow "demand side resources" to participate in wholesale energy markets. These markets are commonly referred to as demand response.
[edit] Demand Response Markets
[edit] NYISO
- Day Ahead Demand Response Program
- Emergency Demand Response Program
- Special Case Resources
[edit] Technology or installation limitations
[edit] Compact fluorescent light bulbs
While Compact fluorescent light bulbs can fit into any socket designed for traditional incandescent bulbs, some lighting fixtures tuck the socket into spaces too compact for CF bulbs, which are still slightly larger than traditional lights.
In an initial house construction, this issue can be completely avoided by taking caution when purchasing or designing light fixtures.
Also, most CF bulbs require additional electronics in order to work with standard dimmer switches or timers.
[edit] Geothermal Heat Pumps
The single greatest issue for GHPs are the installation requirements. They are as follows:
- Available land for installation: Vertical bore systems avoid this as they only need 20ft between wells/columns. Horizontal systems requre substantially more space.
- Structure size: As the house or business increases in size substantially, there is a diminishing return on investment (ROI) as there is the probability that the installed system will require 2 or more main system units as well as additional/duplicate system management implements such as thermostats.
- Heat source/Cooling sink: Impacted mostly by climate, but occasionally by geologic conditions. The ground must have a reasonable constant temperature and there needs to be as high a surface contact as possible for heat exchange to actually take place. This is usually facilitated by constantly introducing water into the horizontal field or in vertical systems by using a desiccant like montmorillonite that absorbs naturally present/flowing water during the early life of the installation.
[edit] Technologies
[edit] Lighting
Type : Energy to Lighting Efficiency
- Incandescent light bulb: 5%-10% (including halogen lamps).
- Fluorescent light bulb: 20%-40% (depending on the exact type).
- Light-emitting diode (LED) 15%-45% (depending on the exact type).
[edit] Heating/Cooling/Hot water
- Geothermal exchange heat pump: From 250% to 350%[1][2] and higher in some experimental designs.
[edit] Smart control
Includes:
- Motion sensor light switches and outdoor lights
- Timer Light Switches
- Fully programmable thermostats
- Whole home computer controlled intelligent device management/automation. See Home automation
[edit] Geothermal exchange heat pump (GHP)
In theory, Heat Pumps (the category also includes air conditioners) are producing heat (or removing heat and placing it elsewhere) at a rate in excess of 100%. This means that there is more heat energy moved around than it would take to produce the same heat energy with an electric element. The reference to the electric element is important as electric heat is accepted as 100% efficient. Due to the laws of thermodynamics, the greater the extreme in temperature, the faster the movement of heat energy.
With this in mind, GHPs are always working with a reasonable to excellent difference in temperature between the coolant and the ground. GHPs that are based on direct expansion technology [3] are usually the most efficient due to the nature of a device that has fewer transitional stages. The previous link shows that a DX heatpump can, in ideal conditions, achieve a COP (Coefficient of Performance) as high as 3.8 or 380% efficient. In a more fundamental form, this means that if you were to compare electric to a DX GHP, you would only have to spend, in ideal conditions, 26% of what you would have to spend to heat with electric baseboards.
Depending on when one installs a GHP (during initial construction or in a retrofit), you will experience a different ROI. Additional sources of variability are: The cost of electricity, local tax rates, the heating and cooling needs based on geographic location and the variability of installation costs from the contractor.
Initial installations can experience a ROI as short as three years and as long as seven years. As an example, the cost of power [4] in the province of New Brunswick, Canada has risen so high that the ROI is easily achieved in less than five years.
An additional note on initial installation, the cost that is be factored against the reduced energy costs is the difference in cost between the systems that are being considered as a heating/cooling solution.
A retrofit installation typically has a larger cost of implementation and therefore will have a longer ROI. The cost of such an endeavour is too variable to post extensive or even expected ROIs for every situation, proceed knowing that the closer a house or structure is to modern forced air standards, the closer to initial construction the ROI will be.
Beyond DX technology, classical closed loop liquid coolant GHPs are easily capable of reaching the same efficiencies. [5] The only detractor is the restrictions on construction that may present themselves using this subform of heat transfer.
[edit] Origin of negawatt
Amory Lovins found a typo while reading a Colorado Public Utilities Commission report, and found the typo "negawatt" (the report had meant "megawatt"). Lovins saw the typo as a way to describe a watt of electricity that wasn't created, due to energy efficiency.[1]
[edit] See also
[edit] External links
- The Negawatt Revolution Keynote Address by Amory Lovins at the Green Energy Conference Montreal 1989
- The Rocky Mountain Institute's home page
- Developing And Diversifying Energy Systems
[edit] References
- ^ Kolbert, Elizabeth. "Mr. Green: Environmentalism's most optimistic guru." The New Yorker, 2007-1-22.
