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外文文獻(xiàn)
Complicated power system in our country, in order to be able to further understand the development situation of power system in our country, to our country electric power system were investigated. Overall status quo of China's electric power system is better, with the growth of economy, electricity demand is also more and more big, but there are regional differences. Power structure in some problems, should adjust the structure of the power supply, should from the following three aspects: one is each kind of power supply especially thermal power need to adjust technological progress; The second is the proportion of hydropower, thermal power and other forms of power generation should be reasonably adjust; 3 it is layout of power supply should be adjusted, too. Reserves of coal resources in our country, but its reasonable distribution. High load such as the east China area has coal, coal in northern most concentrated in the northwest and north China. And is suitable to build hydropower place mostly in the west. Hydropower resources, but the distribution is not reasonable. Should adjust the layout by power grid construction for power resources optimize a vast variety of renewable resources in China
Affected by economic growth, especially the strong industrial production growth, demand for electricity in China to achieve high growth, but our country electricity distribution growth area. Electricity growth according to regional distribution is very uneven, the overall electricity strong growth China's eastern coastal economic developed region, the western region more energy-intensive industrial distribution provinces electricity growth is bigger also, slower growth in central China, China's electric power system load also presents a structural change. Now environmental problems more and more serious, now of the electric power construction must consider this. In the second part introduces the present situation of electric power system in China, the third part is the development trend of power system in our country.
power supply structure adjust the electric power industry in our country's industrial policy purpose is to optimize the power structure, strengthening the construction of power grid. Priority to the development of hydropower, nuclear power, wind power, solar power, biomass and other renewable energy and new energy, while the coal based on the optimization of structure, resource conservation, attaches great importance to environmental protection, raise the level of technical and economic.Big pressure on small measures for improvement of the thermal power industry average single capacity, enhance the overall economic benefits of the industry, improve the environmental benefits. For new energy policies and planning, will lead to lower proportion of thermal power in electric power, increase the proportion of water and electricity, nuclear power, wind power, optimize the electricity structure.Changes in industry structure at the same time, measure the factors of electric power enterprise competitiveness is also changing. Energy-saving power generation dispatching method, to a great extent, changed the competitive landscape industry enterprises; The high proportion of new energy power generation companies, high resource utilization will be more long-term competitive advantage.
In the face of the serious of our country
Our energy resources and the imbalance of the power load distribution, determine the "China" is the inevitable choice of our country. China is focused on conveying hydroelectric power. In accordance with the principle of economy, moderate construction of coal-fired power plant, the implementation xd to east.Send at present, China has entered the stage of full implementation: guizhou province to guangdong 500 kv ac and dc power transmission and transformation projects have been put into production operation, to guangdong power scale has reached 10.88 million kilowatts. Three gorges to east China, guangdong + 500 kv dc power transmission and transformation project has been put into production. Stake, shanxi, shaanxi region send to jing jin tang net capacity increased gradually. North China and the northeast, fujian and east China, each with a batch of network such as central China project has been put into operation, interregional exchange capacity reach 86.2 billion KWH in 2003.As of July 2005, in addition to the hainan has preliminarily realized the networking, preliminary achieved across the optimal allocation of regional resources, more frequency on power exchange between the regional power grid
wind power construction scale is gradually expanding. Starting from "seventh construction of wind farms, by the end of 2004, China has built 43 wind farm, the cumulative installed 1292 units, with a total installed capacity of 764000 kilowatts, accounted for 0.17% of the country's electricity installed. Stand-alone capacity of 2000 kilowatts.
geothermal power generation applications. By the end of 1993, Tibetan geothermal power to reach 28.13 gw, which accounts for 94% of geothermal power generation capacity (including Taiwan); Generating capacity of 97 million KWH, Lhasa grid by about 20%.
solar power began to start. By 1999, cumulative installed capacity of more than 13 mw photovoltaic power generation system. Build capacity of 1 2004 mw of solar power system, this is China and Asia at present a total installed capacity of the grid photovoltaic power generation system, at the same time, also is one of the few in the world of megawatt one of large-scale solar photovoltaic power generation systems.
small hydropower construction made great achievement. By the end of 2000, China has built more than 40000 for small hydropower projects.
the national economy sustained and rapid growth, huge pull function on the power. In the 1970 s, basic in long-term serious power shortage situation in China, the shortage of electricity supply is a major bottleneck restricting the development of economy. With the power industry rapid development, in 1997 began to implement the basic balance of the power supply and demand, supply parts. Entering the new century, with China's implementation of western development strategy, implement active fiscal policy and economic policy of expanding domestic demand, the sustainable development of the national economy and power demand growth also reached record high. After the electricity increased by 9% in 2001, rising to 11.8% in 2002, rising to 15.4% in 2003, rising to 14.8% in 2004. The economically developed Yangtze river delta, the pearl river delta and other coastal areas demand continued strong power. Starting from the second half of 2002, the country's electricity supply and demand situation and hasten is intense, power-generation utilization greatly increased hours (use), local area began to enable power brownouts
unbalanced economic development, make the electricity demand imbalance. Affected by economic growth, especially the strong industrial production growth, demand for electricity in China to achieve high growth, but our country electricity distribution growth area. Electricity growth according to regional distribution is very uneven, the overall electricity strong growth China's eastern coastal economic developed region, the western region more energy-intensive industrial distribution provinces electricity growth is bigger also, slower growth in central China. Main show is:
(1) electricity load is generally higher than electricity consumption growth, is uncertain. Summer performance for load growth fast, winter show the power consumption is growing faster.
(2) with the increase proportion of summer cooling load, the temperature climate forgrowth effect is more and more big, the maximum load, maximum load growth increases randomness, is sensitive to temperature, the greater the thermal field of high temperature season area expands unceasingly, the network has reached the highest load at the same time. In addition to the northeast, northwest, load curve is a double-peak shape it
To optimize the power structure is the proportion of coal is very high, and is growing rapidly in recent years, proportion, further improve the hydropower development rate is low, the proportion of clean power generation installed gross capacity of smaller; Second is 200000 mw and below units more than 100 million kw (4403), one of 100000 mw and below 65.7 million kw (3993), combined with the current small units shut down around the pace of the slowdown in the unit, enterprise should bring along their own fuel increased, coal and fuel oil still possess too high proportion, small unit in operation of 600000 mw and above thermal power unit only 55 units, large unit number is less; Three is in the operation of air cooling unit capacity of about 5 million kilowatts, compared with three norths capacity in water shortage regions, the proportion is low, its water saving advantages did not show up; Four is less cogeneration units, urban central heating rate is 27%; Five is the power load capacity is insufficient, rely mainly on coal-fired thermal power unit load reduction operation, load efficiency is poor.
Electricity production major technical indicators with the international level there is a certain gap. Level not enough advanced thermal power unit parameters, subcritical unit accounted for 40% and above parameters, high pressure, superhigh pressure parameter set (29%), high voltage unit and the following parameters (31%); Only 9.6 million mw supercritical unit, accounting for 2.95% of the total thermal power installed. Domestic economy lags behind that of the corresponding in the large sets of imported units, 300000 mw capacity level, domestic subcritical unit's power supply coal consumption is higher than import unit 4 to 12 g/kWh. 600000 kw capacity level, domestic subcritical unit's power supply coal consumption is higher than import unit 20 to 23 g/kWh, higher than the imported supercritical unit 28 ~ 39.5 g/kWh. In 300000 mw and 600000 mw subcritical unit main, auxiliary engine introduction of digestion process, due to factors such as main, auxiliary engine output, reliability, formed from the standard, design and management requirements increase auxiliaries with margin, led directly to the auxiliary engine run away from economic condition, auxiliary power increases, unit economy decline. Average rate of power grid
resource conditions restrict development. Hydropower in China, coal is abundant, oil and gas resources is insufficient, and the distribution is very uneven. Hydropower resources, the highest in the world, but more than three quarters of the water resources distribution in the west. Proven coal reserves in our country in the world third, with 55% of the world's average per capita reserves. Natural gas and oil reserves per capita in China is only the world average of 11% and 4.5%. New energy such as wind and solar power generation restricted by technical factors, are intermittent energy sources, might be accounted for in the short term is not too much, need to lead positive development.
power are increasing contradictions between development and resources and environment. Electric power production is highly dependent on coal, a large number of development and coal burning caused environmental problems, including the ground subsidence, ground water system is destroyed, the acid rain harm geographic area expands year by year, large amounts of greenhouse gas and solid waste emission, etc. Thermal power needs to cost a lot of fresh water resources, and fresh water resources shortage in our country, per capita is for 1/4 of the world average, and uneven distribution, including an acute shortage of water in north China and northwest regions. At the same time, China's soil and water loss, land desertification in the world and one of the serious environmental pollution. To analysis China's stage of development, the future for several years, is a large number of resources consumed, the conflict between man and nature is very fierce. The current energy consumption way, is our energy, water and environment capacity cannot support.
need to shift the economic growth pattern. Current our country's economy is still belongs to the high input, high consumption, high emission, not harmonious, difficult circulation and low efficiency of the extensive growth pattern. If the electricity growth rates of recent years, the 2020 national electricity demand up to 11 trillion KWH, corresponding power 2.4 billion kw, will be more than 5 billion tons of coal for electricity generation, is six times now, this is clearly impossible. Under the background of sustained, rapid economic growth, economic growth medium and long term to be covered in the GDP figures have risen sharply shortage is gradually revealed, bring economic operation concern directly. Economic growth requires a fundamental shift, to ensure the sustainable development of national economy.Since the reform and opening, through scientific and technological progress and improve efficiency, declining output current consumption in our country, the power consumption from 1980 to 0.21 KWH per unit of output in 2000 fell to 0.151 KWH, down 0.059 KWH. If still can maintain such a decline over the next 20 years, according to the goal of quadrupling GDP in 2020, approximately
improve power grid safety requirements. Power grid into a period of rapid development in our country, the power grid with large transmission power, realize inter-basin adjustment, reduce the reserve capacity, delay the new unit put into production, electric power industry as a whole to reduce costs, improve the efficiency, etc. But with the further expansion of power grid, the increase in the number of factors affect the safety, the technology is more complex, more needs to coordinate, and the accident might spread to a wider range, the damage would be even greater. August 14 with power grid accident caused widespread power outages to ring alarm bells around the world, power grid power higher safety requirements.
漢語(yǔ)文獻(xiàn)
我國(guó)電力系統(tǒng)情況復(fù)雜，為了能夠深入了解我國(guó)電力系統(tǒng)的發(fā)展形勢(shì)，對(duì)我國(guó)電力的系統(tǒng)進(jìn)行了調(diào)查。我國(guó)電力系統(tǒng)的整體現(xiàn)狀比較好，隨著經(jīng)濟(jì)的增長(zhǎng)，電力需求也越來(lái)越大，但是存在地區(qū)的差異。電源結(jié)構(gòu)也存在在一些問(wèn)題，要調(diào)整這種電源結(jié)構(gòu)，需從以下三個(gè)方面著手：一是每一種電源尤其火電需要進(jìn)行技術(shù)進(jìn)步調(diào)整；二是水電、火電及其他發(fā)電形式的比例應(yīng)合理調(diào)整；三是電源布局也應(yīng)調(diào)整。我國(guó)煤炭資源儲(chǔ)藏量不少，但分布極不合理。負(fù)荷高的地方如華東地區(qū)基本沒(méi)有煤，煤大部分集中在西北部或華北北部。而適宜建水電的地方大部分在西部。水能資源不少，但分布不合理。應(yīng)該通過(guò)電網(wǎng)建設(shè)調(diào)整布局使電力資源得到最大優(yōu)化我國(guó)幅員遼闊各種可再生資源比較豐富，要充分利用可再生資源，能夠?qū)崿F(xiàn)綠色電能的效果。
受經(jīng)濟(jì)增長(zhǎng)、尤其是工業(yè)生產(chǎn)增長(zhǎng)的強(qiáng)勁拉動(dòng)，我國(guó)電力需求實(shí)現(xiàn)高速增長(zhǎng)，但是我國(guó)用電增長(zhǎng)地區(qū)分布不均。用電增長(zhǎng)按地區(qū)分布很不平衡，總體來(lái)看我國(guó)東部沿海經(jīng)濟(jì)發(fā)達(dá)地區(qū)用電強(qiáng)勁增長(zhǎng)，西部地區(qū)高耗能產(chǎn)業(yè)分布較多的省區(qū)用電增長(zhǎng)幅度也較大，中部地區(qū)增長(zhǎng)較慢，我國(guó)電力系統(tǒng)的負(fù)荷也呈現(xiàn)出結(jié)構(gòu)性變化。現(xiàn)在環(huán)境問(wèn)題越來(lái)越來(lái)嚴(yán)峻，現(xiàn)在的電力建設(shè)必須考慮這一點(diǎn)。在第二部分介紹我國(guó)電力系統(tǒng)的現(xiàn)狀，第三部分是對(duì)我國(guó)電力系統(tǒng)發(fā)展趨勢(shì)的闡述。
電源結(jié)構(gòu)不斷調(diào)整 我國(guó)電力行業(yè)的產(chǎn)業(yè)政策主旨是優(yōu)化電源結(jié)構(gòu)，加強(qiáng)電網(wǎng)建設(shè)。優(yōu)先發(fā)展水電、核電、風(fēng)電、太陽(yáng)能發(fā)電、生物質(zhì)發(fā)電等可再生能源及新能源，而對(duì)煤電則立足優(yōu)化結(jié)構(gòu)、節(jié)約資源、重視環(huán)保、提高技術(shù)經(jīng)濟(jì)水平。上大壓小的舉措提高了火電行業(yè)平均單機(jī)裝機(jī)容量，增強(qiáng)了行業(yè)的總體經(jīng)濟(jì)效益，提高了環(huán)境效益。對(duì)于新能源的各項(xiàng)政策及規(guī)劃，將引導(dǎo)降低火電在電力中的占比，增加水電、核電、風(fēng)電的比例，優(yōu)化電力結(jié)構(gòu)。在行業(yè)結(jié)構(gòu)變化的同時(shí)，衡量電力企業(yè)競(jìng)爭(zhēng)力的因素也正發(fā)生變化。節(jié)能發(fā)電調(diào)度辦法的出臺(tái)，在很大程度上改變了行業(yè)內(nèi)企業(yè)的競(jìng)爭(zhēng)格局；那些新能源發(fā)電比例高、資源利用率高的企業(yè)將更具長(zhǎng)期的競(jìng)爭(zhēng)優(yōu)勢(shì)。面對(duì)我國(guó)的嚴(yán)峻能源環(huán)境形勢(shì)，“節(jié)能減排”側(cè)重于“節(jié)流”，而對(duì)于新能源的鼓勵(lì)則側(cè)重于“開(kāi)源”?！犊稍偕茉捶ā返念C布，從法律上確認(rèn)了國(guó)家將可再生能源的開(kāi)發(fā)利用列為能源發(fā)展的優(yōu)先領(lǐng)域，該法規(guī)定政府必須制定可再生能源開(kāi)發(fā)利用總量目標(biāo)和采取相應(yīng)措施，推動(dòng)可再生能源市場(chǎng)的建立和發(fā)展。到2020年，我國(guó)小水電總發(fā)電裝機(jī)容量將達(dá)到7500萬(wàn)千瓦，年替代8000萬(wàn)噸標(biāo)準(zhǔn)煤；風(fēng)力發(fā)電裝機(jī)容量可以達(dá)到4000萬(wàn)千瓦，年替代3000萬(wàn)噸標(biāo)準(zhǔn)煤；生物質(zhì)發(fā)電裝機(jī)容量達(dá)到2000萬(wàn)千瓦，年替代2800萬(wàn)噸標(biāo)準(zhǔn)煤；生物油開(kāi)發(fā)可達(dá)到年產(chǎn)2000萬(wàn)噸標(biāo)準(zhǔn)煤；太陽(yáng)能熱水器總集熱面積達(dá)到2.7億平方米，年替代10000多萬(wàn)噸標(biāo)準(zhǔn)煤。專家表示，如能實(shí)現(xiàn)上述發(fā)展目標(biāo)，我國(guó)到2020年可再生能源開(kāi)發(fā)利用總量將達(dá)到3億噸標(biāo)準(zhǔn)煤，約占屆時(shí)一次能源消費(fèi)總量的10%。節(jié)能發(fā)電調(diào)度等政策在很大程度上改變了行業(yè)內(nèi)企業(yè)的競(jìng)爭(zhēng)格局；大機(jī)組比例高、新能源發(fā)電比例高、資源利用率高、煤耗低的“三高一低”企業(yè)，如水電中的長(zhǎng)電、桂冠、川投；火電中華能、大唐、國(guó)電等將更具長(zhǎng)期的競(jìng)爭(zhēng)優(yōu)勢(shì)。風(fēng)電短期內(nèi)業(yè)績(jī)釋放不明顯，但是我們看好其長(zhǎng)期增長(zhǎng)潛力及速度，如銀星能源等。
西電東送和全國(guó)聯(lián)網(wǎng)發(fā)展迅速。我國(guó)能源資源和電力負(fù)荷分布的不均衡性，決定了“西電東送”是我國(guó)的必然選擇。西電東送重點(diǎn)在于輸送水電電能。按照經(jīng)濟(jì)性原則，適度建設(shè)燃煤電站，實(shí)施西電東送。目前，西電東送已進(jìn)入全面實(shí)施階段：貴州到廣東500千伏交、直流輸變電工程已先后投產(chǎn)運(yùn)行，向廣東送電規(guī)模已達(dá)1088萬(wàn)千瓦。三峽到華東、廣東±500千伏直流輸變電工程先后投產(chǎn)。蒙西、山西、陜西地區(qū)向京津唐電網(wǎng)送電能力逐步增加。華北與東北、福建與華東、川渝與華中等一批聯(lián)網(wǎng)工程已經(jīng)投入運(yùn)行， 2003年跨區(qū)交換電量達(dá)到862億千瓦時(shí)。
截至2005年7月，除海南外已經(jīng)初步實(shí)現(xiàn)了全國(guó)聯(lián)網(wǎng)，初步實(shí)現(xiàn)了跨區(qū)域資源的優(yōu)化配置，區(qū)域電網(wǎng)間的電力電量交換更加頻繁，交易類型出現(xiàn)了中長(zhǎng)期、短期、超短期、可中斷交易等多種模式，呈現(xiàn)多樣化的良好局面，由于跨區(qū)跨省電力交易比較活躍，部分聯(lián)網(wǎng)輸電通道長(zhǎng)期保持大功率送電。西電東送、全國(guó)聯(lián)網(wǎng)工程對(duì)調(diào)劑電力余缺、緩解電力供應(yīng)緊張和促進(jìn)資源優(yōu)化配置起到重要作用。
風(fēng)力發(fā)電建設(shè)規(guī)模逐步擴(kuò)大。從“七五”開(kāi)始建設(shè)風(fēng)電場(chǎng)，到2004年底，內(nèi)地已建成43個(gè)風(fēng)電場(chǎng)，累計(jì)裝機(jī)1292臺(tái)，總裝機(jī)容量達(dá)到76.4萬(wàn)千瓦，占全國(guó)電力裝機(jī)的0.17%。單機(jī)容量達(dá)到2000千瓦。
2.2.2地?zé)岚l(fā)電得到應(yīng)用。到1993年底，西藏地?zé)岚l(fā)電的總裝機(jī)達(dá)到28.13兆瓦，約占全國(guó)地?zé)岚l(fā)電裝機(jī)(包括臺(tái)灣在內(nèi))的94%；年發(fā)電量9700萬(wàn)千瓦時(shí)，占拉薩電網(wǎng)約20%。
太陽(yáng)能發(fā)電開(kāi)始起步。至1999年，光伏發(fā)電系統(tǒng)累計(jì)裝機(jī)容量超過(guò)13兆瓦。2004年建成容量為1兆瓦的太陽(yáng)能發(fā)電系統(tǒng)，這是目前中國(guó)乃至亞洲總裝機(jī)容量第一的并網(wǎng)光伏發(fā)電系統(tǒng)，同時(shí)，也是世界上為數(shù)不多的兆瓦級(jí)大型太陽(yáng)能光伏發(fā)電系統(tǒng)之一。
小水電建設(shè)取得巨大成績(jī)。截止到2000年底，全國(guó)已建成小水電站4萬(wàn)多座，裝機(jī)達(dá)2485萬(wàn)千瓦，占全國(guó)水電裝機(jī)的32，4％，占世界小水電開(kāi)發(fā)量的40％以上，年發(fā)電量800億千瓦時(shí)，占全國(guó)水電發(fā)電量的36.27%。
國(guó)民經(jīng)濟(jì)持續(xù)快速增長(zhǎng)，對(duì)電力的拉動(dòng)作用巨大。上世紀(jì)70年代起，我國(guó)基本處于長(zhǎng)期嚴(yán)重缺電的局面，電力供應(yīng)短缺是制約經(jīng)濟(jì)發(fā)展的主要瓶頸。隨著電力工業(yè)快速發(fā)展，1997年開(kāi)始實(shí)現(xiàn)了電力供需的基本平衡，部分地區(qū)供大于求。進(jìn)入新世紀(jì)，隨著我國(guó)實(shí)施西部大開(kāi)發(fā)戰(zhàn)略，實(shí)行積極財(cái)政政策和擴(kuò)大內(nèi)需的經(jīng)濟(jì)方針，國(guó)民經(jīng)濟(jì)持續(xù)發(fā)展，電力需求增長(zhǎng)也屢創(chuàng)新高。繼2001年用電增長(zhǎng)9%之后，2002年增長(zhǎng)11.8%、2003年增長(zhǎng)15.4%、2004年增長(zhǎng)14.8%。經(jīng)濟(jì)較發(fā)達(dá)的長(zhǎng)江三角洲、珠江三角洲等沿海地區(qū)電力需求持續(xù)旺盛。從2002年下半年開(kāi)始，全國(guó)電力供需狀況又趨緊張，發(fā)電裝機(jī)利用率（利用小時(shí)數(shù)）大幅提高，局部地區(qū)開(kāi)始啟用限電措施。2003年～2004年，全國(guó)電力供需平衡繼續(xù)總體偏緊。整體看來(lái)，由于人均發(fā)電裝機(jī)占有量偏低，電力供應(yīng)的高速增長(zhǎng)仍難以滿足更快增長(zhǎng)的電力需求，電力工業(yè)仍存在較大發(fā)展空間。
經(jīng)濟(jì)發(fā)展不平衡，使電力需求不平衡。受經(jīng)濟(jì)增長(zhǎng)、尤其是工業(yè)生產(chǎn)增長(zhǎng)的強(qiáng)勁拉動(dòng)，我國(guó)電力需求實(shí)現(xiàn)高速增長(zhǎng)，但是我國(guó)用電增長(zhǎng)地區(qū)分布不均。用電增長(zhǎng)按地區(qū)分布很不平衡，總體來(lái)看我國(guó)東部沿海經(jīng)濟(jì)發(fā)達(dá)地區(qū)用電強(qiáng)勁增長(zhǎng)，西部地區(qū)高耗能產(chǎn)業(yè)分布較多的省區(qū)用電增長(zhǎng)幅度也較大，中部地區(qū)增長(zhǎng)較慢。主要表現(xiàn)為：
(1)用電負(fù)荷普遍高于用電量增長(zhǎng)，具有不確定性。夏季表現(xiàn)為負(fù)荷增長(zhǎng)快，冬季表現(xiàn)為用電量增長(zhǎng)快。
(2)隨著夏季降溫負(fù)荷所占的比重逐漸加大，氣溫氣候?qū)ψ畲筘?fù)荷的增長(zhǎng)影響越來(lái)越大，使最大負(fù)荷增長(zhǎng)的隨機(jī)性增大，對(duì)溫度的敏感性也越大，高溫季節(jié)的熱場(chǎng)面積不斷擴(kuò)大，各網(wǎng)達(dá)到最高負(fù)荷有同時(shí)性。除東北、西北年負(fù)荷曲線是雙峰形之外，其他各網(wǎng)全年最大負(fù)荷同現(xiàn)在夏季，年內(nèi)季不均衡增大。這是經(jīng)濟(jì)和社會(huì)發(fā)展的特征標(biāo)志之一。
(3)高峰負(fù)荷持續(xù)的時(shí)間短，華東電網(wǎng)全年負(fù)荷超過(guò)95%,最大負(fù)荷的時(shí)間在100h以內(nèi)，超過(guò)90%最大負(fù)荷時(shí)間為200-300h；華中電網(wǎng)全年負(fù)荷超過(guò)95%最大負(fù)荷的時(shí)間在30h以內(nèi)，超過(guò)90%最大負(fù)荷的時(shí)間在120h以內(nèi)，北京供電局0.85倍最高及以上的運(yùn)行天數(shù)為17天，而2001年則為43天。
(4)年平均月不均衡系數(shù)變化不大，但夏季不均衡系數(shù)明顯低于冬季月不均衡系數(shù)，冬夏典型日負(fù)荷率尤其是夏季黃型的負(fù)荷率，日最小負(fù)荷率有明顯上升。我國(guó)現(xiàn)在電力系統(tǒng)發(fā)電能力增長(zhǎng)趨緩，有利于發(fā)揮現(xiàn)有的發(fā)電能力，但是對(duì)今后電力供應(yīng)會(huì)造成影響。現(xiàn)在看來(lái)，全國(guó)綜合利用小時(shí)達(dá)到4860h，大體上是一個(gè)臨界點(diǎn)了，電力平衡處于一種略微偏緊的平衡。局部地區(qū)已出現(xiàn)拉閘限電，福建、安徽省有多余電力；華中電網(wǎng)供需基本平衡，其中河南較為緊張，而江西電力則有余。川渝電網(wǎng)受來(lái)水影響，冬季較緊張，也出現(xiàn)了拉閘限電，東北電網(wǎng)仍然有富余的電力，西北電網(wǎng)供需基本平衡。
進(jìn)一步提高，水電開(kāi)發(fā)率較低，清潔發(fā)電裝機(jī)總?cè)萘克急壤^??；二是20萬(wàn)千瓦及以下機(jī)組超過(guò)1億千瓦（4403臺(tái)），其中10萬(wàn)千瓦及以下有6570萬(wàn)千瓦（3993臺(tái)），加之目前各地小機(jī)組關(guān)停步伐明顯放緩、企業(yè)自備燃油機(jī)組增多，燃煤和燃油小機(jī)組仍占有過(guò)高比重，投入運(yùn)行的60萬(wàn)千瓦及以上火電機(jī)組僅55臺(tái)，大型機(jī)組為數(shù)較少；三是在運(yùn)行空冷機(jī)組容量約500萬(wàn)千瓦，與三北缺水地區(qū)裝機(jī)容量相比，所占比例低，其節(jié)水優(yōu)勢(shì)沒(méi)有體現(xiàn)出來(lái)；四是熱電聯(lián)產(chǎn)機(jī)組少，城市集中供熱普及率為27％；五是電源調(diào)峰能力不足，主要依靠燃煤火電機(jī)組降負(fù)荷運(yùn)行，調(diào)峰經(jīng)濟(jì)性較差。
電力生產(chǎn)主要技術(shù)指標(biāo)與國(guó)際水平還有一定差距。火電機(jī)組參數(shù)等級(jí)不夠先進(jìn)，亞臨界及以上參數(shù)機(jī)組占40％，高壓、超高壓參數(shù)機(jī)組占29％，高壓及以下參數(shù)機(jī)組占31％；超臨界機(jī)組僅960萬(wàn)千瓦，占火電裝機(jī)總量的2.95%。國(guó)產(chǎn)大機(jī)組的經(jīng)濟(jì)性落后于相應(yīng)進(jìn)口機(jī)組，30萬(wàn)千瓦容量等級(jí)，國(guó)產(chǎn)亞臨界機(jī)組的供電煤耗比進(jìn)口機(jī)組高4～12g/kWh；60萬(wàn)千瓦容量等級(jí)，國(guó)產(chǎn)亞臨界機(jī)組的供電煤耗比進(jìn)口機(jī)組高20～23g/kWh，比進(jìn)口超臨界機(jī)組高28～39.5g/kWh。在30萬(wàn)千瓦、60萬(wàn)千瓦亞臨界機(jī)組主、輔機(jī)引進(jìn)消化過(guò)程中，由于主、輔機(jī)出力、可靠性等因素影響，形成從標(biāo)準(zhǔn)上、設(shè)計(jì)和管理上要求增大輔機(jī)配備裕度，直接導(dǎo)致輔機(jī)運(yùn)行偏離經(jīng)濟(jì)工況，廠用電升高，機(jī)組經(jīng)濟(jì)性下降。電網(wǎng)的平均損失率為7.71%,尚有進(jìn)一步降低的空間。清潔煤發(fā)電技術(shù)、核電技術(shù)的進(jìn)步較慢，大型超(超)臨界機(jī)組、大型燃?xì)廨啓C(jī)、大型抽水蓄能設(shè)備及高壓直流輸電設(shè)備等本地化水平還比較低，自主開(kāi)發(fā)和設(shè)計(jì)制造能力不強(qiáng)，不能滿足電力工業(yè)產(chǎn)業(yè)升級(jí)和技術(shù)進(jìn)步的需要。
資源條件制約發(fā)展。我國(guó)水能、煤炭較豐富，油、氣資源不足，且分布很不均衡。水能資源居世界首位，但3/4以上的水能資源分布在西部。我國(guó)煤炭探明保有儲(chǔ)量居世界第三位，人均儲(chǔ)量為世界平均水平的55%。我國(guó)天然氣和石油人均儲(chǔ)量?jī)H為世界平均水平的11%和4.5%。風(fēng)能和太陽(yáng)能等新能源發(fā)電受技術(shù)因素限制，多為間歇性能源，短期內(nèi)所占比重不可能太高，需要引導(dǎo)積極開(kāi)發(fā)。
電力發(fā)展與資源、環(huán)境矛盾日益突出。電力生產(chǎn)高度依賴煤炭，大量開(kāi)發(fā)和燃燒煤炭引發(fā)環(huán)境生態(tài)問(wèn)題，包括地面沉陷、地下水系遭到破壞，酸雨危害的地理面積逐年擴(kuò)大，溫室氣體和固體廢料的大量排放等?；鹆Πl(fā)電需要耗用大量的淡水資源，而我國(guó)淡水資源短缺，人均占有量為世界平均水平的1/4，且分布不均，其中華北和西北屬嚴(yán)重缺水地區(qū)。同時(shí)，我國(guó)也是世界上水土流失、土地荒漠化和環(huán)境污染嚴(yán)重的國(guó)家之一。以我國(guó)的發(fā)展階段分析，未來(lái)若干年，是大量消耗資源、人與自然之間沖突極為激烈的時(shí)期。目前的能源消耗方式，是我國(guó)能源、水資源和環(huán)境容量無(wú)法支撐的。
經(jīng)濟(jì)增長(zhǎng)方式需要轉(zhuǎn)變。當(dāng)前我國(guó)經(jīng)濟(jì)尚屬于高投入、高消耗、高排放、不協(xié)調(diào)、難循環(huán)、低效率的粗放型增長(zhǎng)模式。若按近幾年的用電增速計(jì)算，2020年全國(guó)電力需求將高達(dá)11萬(wàn)億千瓦時(shí)，相應(yīng)發(fā)電裝機(jī)24億千瓦，發(fā)電用煤將超過(guò)50億噸，是目前的6倍，這顯然是不可能的。在持續(xù)、快速的經(jīng)濟(jì)增長(zhǎng)背景下，經(jīng)濟(jì)增長(zhǎng)方式中長(zhǎng)期被GDP數(shù)字大幅上升掩蓋的不足正逐漸顯現(xiàn)，直接給經(jīng)濟(jì)運(yùn)行帶來(lái)隱憂。經(jīng)濟(jì)增長(zhǎng)方式需要根本性轉(zhuǎn)變，以保證國(guó)民經(jīng)濟(jì)可持續(xù)發(fā)展。改革開(kāi)放以來(lái)，通過(guò)科技進(jìn)步和效率提高，我國(guó)產(chǎn)值單耗不斷下降，單位產(chǎn)值電耗從1980年的0.21千瓦時(shí)降至2000年的0.151千瓦時(shí),下降了0.059千瓦時(shí)。假如未來(lái)20年仍能保持這樣的下降幅度，按照2020年GDP翻兩番的目標(biāo)，約可減少電耗3.22萬(wàn)億千瓦時(shí)。節(jié)能提效空間巨大。
電網(wǎng)安全要求不斷提高。我國(guó)電網(wǎng)進(jìn)入快速發(fā)展時(shí)期，大電網(wǎng)具有大規(guī)模輸送能量，實(shí)現(xiàn)跨流域調(diào)節(jié)、減少備用容量，推遲新機(jī)組投產(chǎn)，降低電力工業(yè)整體成本，提高效率等優(yōu)點(diǎn)。但隨著目前電網(wǎng)進(jìn)一步擴(kuò)展，影響安全的因素增多，技術(shù)更加復(fù)雜，需要協(xié)調(diào)的問(wèn)題更多，事故可能波及的范圍更廣，造成的損失可能會(huì)更大。8·14美加電網(wǎng)事故造成大范圍停電給全世界敲響了警鐘，大電網(wǎng)的電力安全要求更高。