<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2021 Workiva-->
<!--r:7e7a5f22-9275-4309-bbb9-1fc4e360c9c9,g:99db0ed9-e861-4881-885b-3667737c3d66-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.nrgenergy.com/role/CoverCover" xlink:type="simple" xlink:href="nrg-20210506.xsd#CoverCover"/>
  <link:presentationLink xlink:role="http://www.nrgenergy.com/role/CoverCover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_CoverAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_3a08b07f-603c-439a-84d7-f672a0277ffc" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentType"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_DocumentType_3a08b07f-603c-439a-84d7-f672a0277ffc" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_1e3428bc-e12b-48ba-89e3-c86bfa288912" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityRegistrantName"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityRegistrantName_1e3428bc-e12b-48ba-89e3-c86bfa288912" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_bd62f422-23ea-4433-81b5-34d7e1c8ae5d" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentPeriodEndDate"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_DocumentPeriodEndDate_bd62f422-23ea-4433-81b5-34d7e1c8ae5d" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_bbc00e2c-609b-447b-b27d-f5170cfbbaa8" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityCentralIndexKey"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityCentralIndexKey_bbc00e2c-609b-447b-b27d-f5170cfbbaa8" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_9b00a976-3947-4c0e-8d7e-d4b2720183e0" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_AmendmentFlag"/>
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_AmendmentFlag_9b00a976-3947-4c0e-8d7e-d4b2720183e0" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_59e98125-63ac-4a36-8b44-d248ee64c175" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityIncorporationStateCountryCode_59e98125-63ac-4a36-8b44-d248ee64c175" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_13a8f384-8aba-4729-9d07-b243d2950f53" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityFileNumber"/>
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityFileNumber_13a8f384-8aba-4729-9d07-b243d2950f53" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_175ec53b-78a3-492f-b1b6-a0f912061892" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityTaxIdentificationNumber_175ec53b-78a3-492f-b1b6-a0f912061892" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_eb5d494d-2270-442e-bae0-64b8d1d6bbd9" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressAddressLine1"/>
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityAddressAddressLine1_eb5d494d-2270-442e-bae0-64b8d1d6bbd9" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_123a146a-ba54-45a8-8172-d7ccc1c72bb3" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressCityOrTown"/>
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityAddressCityOrTown_123a146a-ba54-45a8-8172-d7ccc1c72bb3" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_e21f32d1-bab0-4a54-86c1-ca7e0d26ccfe" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressStateOrProvince"/>
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityAddressStateOrProvince_e21f32d1-bab0-4a54-86c1-ca7e0d26ccfe" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_4b56b257-335f-463f-9a6b-6391d070cb29" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityAddressPostalZipCode"/>
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityAddressPostalZipCode_4b56b257-335f-463f-9a6b-6391d070cb29" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_c9fd4a4f-174c-4eb2-b556-adad3696650a" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_CityAreaCode"/>
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_CityAreaCode_c9fd4a4f-174c-4eb2-b556-adad3696650a" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_d7e08dcd-4810-4f18-abe2-7ab80936a93c" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_LocalPhoneNumber"/>
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_LocalPhoneNumber_d7e08dcd-4810-4f18-abe2-7ab80936a93c" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_99bbfe1d-7f16-44b1-b7f2-fee9094077c5" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_WrittenCommunications"/>
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_WrittenCommunications_99bbfe1d-7f16-44b1-b7f2-fee9094077c5" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_637cdfd4-ea16-41f3-a694-608fa561bf19" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_SolicitingMaterial"/>
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_SolicitingMaterial_637cdfd4-ea16-41f3-a694-608fa561bf19" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_76fdedea-0782-4c95-bfbb-36f9b0c2037e" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_PreCommencementTenderOffer"/>
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_PreCommencementTenderOffer_76fdedea-0782-4c95-bfbb-36f9b0c2037e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_f2e39f53-c80a-4e61-ba54-e03cb41ba80b" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_f2e39f53-c80a-4e61-ba54-e03cb41ba80b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_155b1e4a-1e60-48ab-add8-61c0a2267fbe" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_Security12bTitle"/>
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_Security12bTitle_155b1e4a-1e60-48ab-add8-61c0a2267fbe" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_4ad7467b-d8a4-47eb-aab4-fba5e8d40b6c" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_TradingSymbol"/>
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_TradingSymbol_4ad7467b-d8a4-47eb-aab4-fba5e8d40b6c" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_b375d1d7-3450-4ba1-8fcd-a520f74dc8bd" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_SecurityExchangeName"/>
    <link:presentationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_SecurityExchangeName_b375d1d7-3450-4ba1-8fcd-a520f74dc8bd" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_597cdee9-a519-41da-8207-e25060ad4cdf" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:presentationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_7e1a1f9d-24b8-4490-9b17-9d2e09fb66d2" xlink:to="loc_dei_EntityEmergingGrowthCompany_597cdee9-a519-41da-8207-e25060ad4cdf" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
  </link:presentationLink>
</link:linkbase>
