Have you heard the bull**** claim that "renewables are great but they aren't enough"?
Have you heard the bull**** claim that "renewables are great but they aren't enough"?
This is a common bit of misinformation that swirls around the public consciousness, perverting the ability of the public to make informed choices on how we proceed to address our energy security and climate change needs. This is a detailed analysis matching real world demand and the known operational profile of renewable energy sources. It clearly shows that claims such as "renewabes can't do it" or "renewables aren't enough" are nothing but balderdash and poppycock.
These false beliefs that are being nurtured by political and economic forces that stand to lose power and money if we focus our efforts on the renewable, sustainable solution to our energy issues.
Equally important is the fact that not only CAN renewables do the job, but they can do it for less money, more reliably, with far fewer external costs, and much much lower risks than the only other non-carbon contenders - coal with carbon capture/sequestration and nuclear power.
The claim is NOT being made that this would be an easy task. Nor is the claim made that the modeling in the paper is perfect representation of all geographic areas and the specific resources that would be available to meet demands in those areas; for example, there will be areas where wave/current/tidal or biomass are more important than solar, or where storage options like pumped hydro and compressed air storage are more appropriate than standard hydro.
What the paper does demonstrate is the fallacy of the idea that renewable energy resources are not up to the task. We have a wide range of technologies sitting on the shelf available to meet demand and it is good to be aware of their potential.
A case study for California in 2020
Graeme R.G. Hoste
Michael J. Dvorak
Mark Z. Jacobson
Stanford University
Department of Civil and Environmental Engineering
Atmosphere/Energy Program
Abstract
In 2002 the California legislature passed Senate Bill 1078, establishing the Renewables Portfolio Standard requiring 20 percent of the state’s electricity to come from renewable resources by 2010, with the additional goal of 33% by 2020 (California Senate, 2002; California Energy Commission , 2004). More recently, some legislative proposals have called for eliminating 80% of all carbon from energy to limit climate change to an ‘acceptable level’. At the passing of the 2002 California bill, qualifying renewables provided less than 10% of California’s energy supply (CEC, 2007). Several barriers slow the development of renewables; these include technological barriers, access to renewable resources, public perceptions, political pressure from interest groups, and cost, to name a few. This paper considers only one technological barrier to renewables: integration into the grid.
Many renewable resources are intermittent or variable by nature—producing power inconsistently and somewhat unpredictably—while on the other end of the transmission line, consumers demand power variably but predictably throughout the day. The Independent System Operator (ISO) monitors this demand, turning on or off additional generation when necessary. As such, predictability of energy supply and demand is essential for grid management. For natural gas or hydroelectricity, supplies can be throttled relatively easily. But with a wind farm, power output cannot be ramped up on demand. In some cases, a single wind farm that is providing power steadily may see a drop in or complete loss of wind for a period. For this reason, grid operators generally pay less for energy provided from wind or solar power than from a conventional, predictable resource.
Although wind, solar, tidal, and wave resources will always be intermittent when they are considered in isolation and at one location, several methods exist to reduce intermittency of delivered power. These include combining geographically disperse intermittent resources of the same type, using storage, and combining different renewables with complementary intermittencies (e.g., Kahn, 1979; Archer and Jacobson, 2003, 2007). This paper discusses the last method: integration of several independent resources. In the pages that follow, we demonstrate that the complementary intermittencies of wind and solar power in California, along with the flexibility of hydro, make it possible for a true portfolio of renewables to meet a significant portion of California’s electricity demand. In particular, we estimate mixes of renewable capacities required to supply 80% and 100% of California’s electricity and 2020 and show the feasibility of load-matching over the year with these resources. Additionally, we outline the tradeoffs between different renewable portfolios (i.e., wind-heavy or solar-heavy mixes). We conclude that combining at least four renewables, wind, solar, geothermal, and hydroelectric power in optimal proportions would allow California to meet up to 100% of its future hourly electric power demand assuming an expanded and improved transmission grid.
To download entire report:
http://www.stanford.edu/group/efmh/jacobson/Articles/I/CombiningRenew/HosteFinalDraft
This is a repost of an OP from 2010. The original thread is a priceless visit with tombstoned DrGreg (who coincidentally shares so many unique traits with PawW).
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x258338
= new reply since forum marked as read
